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[[quoteright:332:[[VideoGame/TheLegendOfZeldaSkywardSword http://static.tvtropes.org/pmwiki/pub/images/rupoor_7777.jpg]]]]
[[caption-width-right:332:[-"[[PokeThePoodle Damn, now I can't make the payment on my horse]]."-] ]]

-> ''"This will either make us really super, or really sick."''
-->-- '''Pac-Man and Mrs. Pac-Man''', ''[[WesternAnimation/PacMan Pac-Man: The Animated Series]]''

An item which harms the player who picks it up or uses it instead of helping them. Differs from PowerUpLetdown in that the harm it causes is direct and intentional, rather than from a design flaw.

So, if it's harmful, why would anyone pick it up or use it? Players don't mean to, but poison mushrooms have four main ways of getting around that:

# In games where immediately useful items randomly drop from killed enemies or other things, having them sometimes be poison mushrooms serves to punish players for blindly chasing down items as soon as they appear.
# Sometimes they just wait in strategic locations for hapless players to stumble into them, in which case they serve as an obstacle to be avoided. (Which raises questions: why would your character go out of their way to pick up something harmful? Or are we to understand that they literally absorb all in-game powerups via skin contact?)
# Other times, they try to look similar to a beneficial item to trick a player into taking it. Beneficial and harmful items may [[PaletteSwap differ only]] [[ColorCodedForYourConvenience in color]], which hurts players with poor color vision or a monochrome display.
# It could also be an item that has [[RandomEffectSpell random effects]], some of which are negative.

Whatever their method, it's a PowerUp that powers you down instead. Contrast with ChestMonster, which is a monster that disguises itself as a PowerUp or other item, and PowerupLetdown, which is a PowerUp with positive effects, just not positive enough to be useful.

Not to be confused with a very large mushroom that [[UsefulNotes/NuclearWeapons is even more deadly]]. Or with actual fungi that are poisonous, such as destroying angels.



[[folder:Action Adventure]]
* The arcade game ''MagicSword'' had plenty of powerups lying around, from stronger weapons, to gaining an infinite projectile attack for some time, to invincibility. And then there is a pair of scissors: pick it up, and your companion is instantly killed.
* Several games in the ''Franchise/{{Castlevania}}'' series had, alongside the usual food items used to restore health, several rotten food items like "Rotten Meat" and "Spoiled Milk". In ''VideoGame/CastlevaniaDawnOfSorrow'', equipping a Ghoul soul allowed Soma to eat them safely. After which, against logic, they would heal disproportionately large amounts of heath -- apparently, to a ghoul, spoiled milk is more nutritious than an entire turkey is to a human.
** The Flesh Golem soul had the same effect in the previous game, ''VideoGame/CastlevaniaAriaOfSorrow''. It's a kind of [[InvertedTrope inversion]] of ReviveKillsZombie.
** ''Vampire Killer'' had red books that would increase prices in the level's {{Dungeon Shop}}s, the opposite effect of the white books.
* ''VideoGame/TheLegendOfZeldaPhantomHourglass'' features "Rupoors", which would somehow ''reduce'' the number of Rupees Link is currently carrying when found. A minor key version of the series' trademark ItemGet fanfare would play when a Rupoor was found, complete with Link holding the item above his head but looking none too pleased about it. One area in the game consists of a maze with Rupoors for walls, requiring Link to walk carefully to avoid them. And to make it more difficult, Keese are flying around the area -- and half of your projectile weapons pick up Rupoors.
** They also appear in ''VideoGame/TheLegendOfZeldaFourSwords'', though rather than directly taking away your Rupees, they make you drop them (allowing other players to steal them).
** They also appear in ''VideoGame/TheLegendOfZeldaSkywardSword'' in the digging minigame. The look on Link's face (seen in the page image) when you pick one up is [[FunnyMoments priceless]].
*** [[AndThatsTerrible And that's a little bit sad.]]
** ''VideoGame/TheLegendOfZeldaTwilightPrincess'' has Purple Chus, which leave behind Purple Chu Jelly when killed. Other types of Chu Jelly are very useful, either restoring a good amount of health or as a Lantern Oil substitute, so Purple Jelly should have a good effect too, right? Wrong, they have a ''random'' effect: while they can heal a random amount of Hearts, they can also ''hurt you'', even taking you down to one Heart. The Nasty Soup, which can be gotten where you get the Lantern, has the same effect. The main purposes of Purple Chus are to make you fight a Chu without getting anything good out of it, or to have them in the same area as useful Chus, forcing you to kill the useful ones and grab their jelly before the purple ones absorb them and take away their useful qualities.
*** However, since the purple chu jelly cannot outright kill you, it is best used while low on health so if you get the negative effects, nothing will happen.
** ''VideoGame/TheLegendOfZeldaOcarinaOfTime'' and ''VideoGame/TheLegendOfZeldaMajorasMask'': The Poes have the same effect when consumed.
* In ''VideoGame/CaveStory'', equipping the Nemesis weapon essentially turns experience crystals into this. At level 1, the Nemesis is a powerful weapon. Collecting 1 EXP will level it "up" to level 2: a weaker Nemesis with shorter range and less damage. Collecting 1 more EXP will bring it to level 3: rubber ducks with short range that do 1 HP of damage.
* The ''{{Superman}}'' game for the NES had this in the form of green and red Kryptonite, which sapped your energy instead of giving it like the blue power crystals.
* ''VideoGame/LuigisMansion'''s minibosses tossed one of these when they hit low hp. Since they bounce randomly and cut off your vacuum, they'd prevent good runs if you were unlucky.
* ''[[Creator/LJNToys The Uncanny X-Men]]'' had magnets which, if picked up, paralyzed you for a ridiculous amount of time. How long you stay frozen is anyone's guess; you ''will'' die before it wears off.

[[folder:Action Game]]
* The ''VideoGame/{{Bomberman}}'' series has the Skull item, which, when picked up, will temporarily give the player a randomly chosen negative effect, such as inability to drop bombs, the inability to NOT drop bombs, slow motion, invisibility (worse than you might think), and a few others. There is a small silver lining, however; you can share or transfer (depending on the game) the effects of the Skull item with another player by touching him or her.
** Though this is VERY dependent on the individual game's list of possible effects, getting the skull could be a GOOD thing. In ''Bomberman 64'', the effects were split 50/50 good to bad; for example, one possible outcome was you would instantly get full power bombs (with blue super sized explosions.) Another one set you on fire, making you able to kill anyone by touching them... but you'd have to move quick because you would burn to death eventually. Another made you absolutely tiny, but super fast.
* ''VideoGame/{{Bomberman}} 64'' and ''Bomberman 64: The Second Attack!'' have "Bomb-Down," "Sandal," and "Fire-Down" items, which lower the amount of bombs you can place, your speed, and the blast radius of your bombs. These also occur throughout the multiplayer modes of most ''Bomberman'' games. ''Bomberman 64'' also featured an "Evil" item, which activated a stage-wide effect potentially affecting all players. Some effects include a tornado, maxing out everyone's bomb count and explosion size, shuffling the positions of all players, and an "evil disco light" that saturated the screen with bright colours, making it hard to see the action.
** They became useful in one specific section of ''The Second Attack!" which required the player to cross the reactor core of a spaceship. Reducing the Blast Radius to zero was the only way to safely cross the otherwise lethal reactor fluid. At zero radius, ice bombs would not blowback on the player if they were careful.
* The ZX Spectrum/Commodore 64 game ''Bounder'' has powerup tiles. Unless you have prior knowledge, a given powerup tile can't be told apart from a trap tile. Worse, the game is an auto scroller, where these powerup tiles appear in the path of where you need to land on each bounce.
* If you pick up one of these in ''Ferazel's Wand'', it's pretty much your own fault, given that they're black with a skull. They're an instant kill, and are typically buried in soft ground (visibly) as an obstacle to digging.
* In ancient Atari 2600 game ''Fast Food'', among the delicacies flying at increasingly high speeds towards your disembodied mouth avatar were green pickles and purple pickles. Green pickles were the most valuable food to devour. Purple pickles made you lose a life.
* In ''VideoGame/FeedingFrenzy'', some of the smallest fish are radioactive and [[SicklyGreenGlow glow yellowish green]]. In the first game, eating one causes the player's controls to stop responding for a brief period, leaving his fish immobile and an easy target for a larger fish. In ''Feeding Frenzy 2'', it's even more disconcerting, since eating one causes the player's controls to operate in reverse.
* ''VideoGame/TheTowerOfDruaga'' has the Potion of Energy Drain and the Potion of Death, the latter of which makes the timer run out faster. Also, not picking up the Balance on any of the five floors that have one will turn the item on the next floor into an "Evil" item.
* ''VideoGame/ZombiesAteMyNeighbors'' has the Mystery Potion give random effects. Most of its effects are beneficial (mimicking those of Speed Shoes, Red and Blue Potions, or First-Aid Kits), but they can also damage you when you drink them. The worst effect, however, is Mr. Hyde, which turns the player briefly into an uncontrollable monster who kills any victims he touches.

[[folder:Adventure Game]]
* In ''{{Gobliiins}}'', many items Dwayne can pick up will harm him and make him lose some of the energy bar. Sometimes, he will ''deliberately strike himself with the object''.
* An old ''Series/TheAddamsFamily'' game, ''Fester's Quest'' for the NES, had red power downs for your gun and whip, as well as the blue powerups.
* In ''Ravenskull'', you can't tell the effects of a scroll or potion without trying it out. Some that you can get are a Lightning Strike Scroll that kills you, a Thief Potion that, as its name suggests, empties your inventory of any items you currently hold (including the potion itself!) and an Energy Drain scroll that reduces your health every square you move instead of every ten. For HundredPerCentCompletion, you have to use all of these.
* ''VideoGame/SpaceQuestIVRogerWilcoAndTheTimeRippers'' comes from a long series where nearly every item you found had a plot-important use. Yet in this game, early on, you can find a piece of Unstable Ordinance. If you keep it in your inventory while moving to the next zone, you explode and die. Your only option was to put it back where you got it from... for which you received praise and points for doing something smart.
* In the Super Nintendo version of ''VideoGame/DragonsLair'', you can pick up a Shuriken. Basically, when you throw it, it arcs upward and comes back around to hit anyone it didn't already... Including you. That's right: A weapon that can kill you when you use it. Considering you could be on a moving platform with enemies flying around you, and you can only strike downwards, it's pretty much the worst weapon you could have in a game like this.
* ''VideoGame/IndianaJonesAndHisDesktopAdventures'': Sometimes, you'll be given tequila at the bar. Drink it, and you lose health.
* In ''[[WesternAnimation/TopCat Top Cat in Beverly Hills Cats]]'', fresh fruit gives you health and rotten fruit takes it away.

[[folder:Beat Em Up]]
* ''VideoGame/TigerRoad'' had you regain health from gourds. Some gourds cost you health instead of restoring it; these could be identified by one feature -- they were upside-down.

[[folder:Driving Game]]
* Fake Item Boxes in [[VideoGame/MarioKart64 Mario Kart 64 and beyond]] do about the same thing as Poison Mushrooms, whereas the normal item boxes are rainbow-colored or bluish and have a "?" while a fake one will be red and have a "ż". Both blocks look exactly the same from a distance (the fake one changing when you get closer), but most players can avoid them by memorizing where real items boxes should appear. The TropeNamer itself appears in the SNES original. The boxes can also be detected, at least in the DS version, by checking the game map. The fake ones appear different than the regular ones.
** The Wii game had a storm cloud item. It floated over your head, charging up lightning. If you didn't give it away by hitting somebody else in time, it would electrocute and shrink you.
*** One small benefit from the storm cloud is a constant speed boost. While the intention of this is to allow players to catch up to another player to pass it off, the boost also lets you drive off track without slowing down, allowing you to take some nice shortcuts especially in the final lap.
* ''VideoGame/{{Carmageddon}}'' had Pinball Mode, which caused you to bounce off objects at increased speed, causing thousands of damage in the first game and probably wrecking you instantly in the sequel. The best thing you could do was sit motionlessly and hoping nobody would hit you. There was also Bouncy Bouncy (your car jumps every few seconds), Jelly Suspension (your car wobbles and tips over), Jupiter Gravity (good luck getting uphill), and the second game has a ball and chain that attaches to your car and Ethereal Pedestrians (can't run over them, so you can't get extra time on your clock for 30 seconds - oops). Not to mention the Drugs, Miniature Pedestrians, Turbo Opponents, basic exploding powerups, Hot Rod (speed boost combined with 'wheelie' suspension, great for blasting into a wall at 600 kph), Greased Tires and the various powerups that crumple up your car or make it break in two.
** Several of these "bad" powerups can be used for good. The ball-and-chain thing isn't practical to use, but powersliding into a group of pedestrians with it is a guaranteed ticket to LudicrousGibs land, and you can detach it at will anyway. Hot Rod is a useful on-demand turbo if used in small doses; also, combined with the tires-stick-to-everything powerup, it's a great way to climb walls (it lifts the nose of the car). And Pinball isn't evil just to you - everything in the game starts bouncing around. Send a ped into a group of others and they'll pinball themselves into pulps, or hit an opponent so that you pinball away to safety while they pinball into an obstacle-filled area, and watch them get wrecked in a second or two.
** The second game lets you buy any car you wrecked in a race. This is a good thing unless you end up buying a bad car, wasting all of your money and being worse off. Hint: almost everything you could buy in the early game is worse than your starting car. This becomes a problem near the end, where you ''need'' something very heavy to kill your opponents (who at that point are driving enormous logging trucks and buses with rocket engines) but almost all of the heavy vehicles are either insanely slow, have terrible driveability, get stuck under or between scenery all the time or all of the above. Then there are the racing missions which have the opposite problem: you need to figure out which cars have high speed and good handling.

[[folder:Fighting Game]]
* In ''VideoGame/SuperSmashBros Melee'' and ''Brawl'', Super Mushrooms made your character grow, while Poison Mushrooms made you shrink. The latter could be identified from the former by a slightly darker color and a slightly meaner expression, with the outer corners of the Poison Mushroom's eyes turned [[TsurimeEyes upward]] rather than [[TaremeEyes downward]]. However, this difference may not be obvious when the camera is zoomed out enough.
** The Hammer present in both games and the Golden Hammer in Brawl both have a chance of being defective and completely harmless, which is a bit problematic when you can't voluntarily get rid of them. It's especially bad in the case of the former, as the head of the hammer falls off, afterwhich it can be used as an extremely powerful throwing weapon, with the most likely target being the defenseless wielder of the broken hammer (Now a useless stick). The Golden Hammer doesn't have such complications, but you can probably buy one in real life: The ''Golden'' Piko Piko Hammer. Complete with the cute squeaky sounds.
** The Lightning Bolt item in Super Smash Bros Brawl shrinks opponents to make them easier to knock out. Then it has the ability to shrink YOU and not the others. Or it may make them all grow giant instead, leaving you in the midst of massive enemies.
** The Metal Box is somewhat of a double-edged sword rather than a complete Poison Mushroom. Getting knocked off the platform while in "Metal" mode will result in you struggling to return to the area as it makes you heavy and... just that.
** And the stopwatch in Brawl, let your opponents move slowly so you can hit them easier. But there's a chance that ALL players can be slowed...and also, JUST YOU be slowed.
* ''VideoGame/DissidiaFinalFantasy'' has Summon Stones you can equip on your fighters which have various effects when activated. However, a couple of the more nostalgic characters have questionable effects.
** The Chocobo runs across the screen randomly jumbling each digit in both your own and your enemy's [[BreakMeter brave meter]], which often results in both players getting either a massive boost or a royal screw-over.
** The Moogle summon will randomly select an ability from any other summon in the game, which, coupled with poor timing, can result in the player getting hosed by a usually-beneficial effect (like Alexander's bravery-freeze when your brave is at or near 0).
** When [[VideoGame/FinalFantasyV Gilgamesh]] is called, he will either use Excalibur to triple your bravery, or Excalipoor to [[HPToOne reduce your brave to 1]]. "I feel so betrayed..."

[[folder:First Person Shooter]]
* ''VideoGame/DeusEx'' lets you smoke and drink booze. Smoking whittles away at your health, while the booze blurs your screen and sways your view for a time. While nothing forces the player to try either booze or cigarettes, the assumption that these droppable items must have some actual ''use'' may draw naive souls in...
** Alcoholic drinks are healing items, though. If you're hurt, you can find a safe spot, down beer, wine and/or liquor, and recover some health (it works like any other food item), and just wait for the effects of blurred vision and swaying screen to go away (which is only a matter of seconds; [[AllThereInTheManual it's explained that]] [[HyperactiveMetabolism your nano-machines make you go through the effects of drunkenness much faster than a normal human]]).
*** The Cigarettes can actually ''kill'' JC if he chain-smokes a truely heroic quantity of them; on the order of chain-smoking ten whole packs at once (because each time you smoke, you consume an entire pack, and each pack deals you 10 health damage to the torso.)
*** Both of the above (minus the cigarettes) are carried over into the prequel, ''VideoGame/DeusExHumanRevolution''.
* ''VideoGame/SystemShock 2'' features various alcoholic beverages and cigarettes aboard the ships. The booze would mildly heal you at the cost of some of your [[ManaMeter psychic power points,]] and cigarettes would simply take a point off of your HP.
* In ''VideoGame/{{BioShock|1}}'', you can eat and drink all sorts of food items lying around. Drinking alcohol restores HP at the cost of EVE, and if you drink too much, you get drunk and the screen blurs for a little while. Smoking has the inverse, taking off some health to restore eve. Admittedly not the same type of poison mushroom as elsewhere, but given that you may need some eve, players may intentionally harm themselves on one or the other to get a quick boost.
** ''VideoGame/BioShockInfinite'' has rotten food, which uses the same icon as its respective healing item and damages you if you eat it. Best check for mold before you eat things out of a trashcan.
* ''VideoGame/RiseOfTheTriad'' has the Shrooms Mode powerdown and the annoying (and depending on where it's located, potentially deadly) Elasto Mode powerup. Shrooms Mode makes shooting straight virtually impossible (and will probably make you feel a bit sick). Elasto Mode makes you bounce off solid objects and drastically reduces your friction with the ground. Given all the hazards in the game, you don't want to wind up picking up an Elasto Mode powerup in a large number of the areas in the game.
** One of the secret levels only reachable via warp cheats includes large rooms full of the Shrooms powerdown, floors filled with bounce pads and little else. It is aptly named the ''Vomitorium''.
* ''VideoGame/PathwaysIntoDarkness'' has the poisonous Brown Potion that causes you to lose health until you consume a rare blue potion, an Alien Artifact that you need to open the exit also drains your health unless you put it in the Lead Box, and a red cape that essentially gives you a reverse bullet time effect. [[GuideDangIt The kicker?]] [[ForbiddenChekhovsGun Using all of these items is required to complete the game.]]

[[folder:Four X]]
* The ''VideoGame/{{Civilization}}'' series (and many subsequent generations of turn-based strategy game) feature the so-called "Goody Huts" -- old dwellings unaffiliated with any faction that, when explored, may turn out to contain scrolls of ancient knowledge, secret treasures, nomads or tribespeople who are sick of living in the ruins... or a barbarian hideout that is none too thrilled with your intrusion. (''Civ V'' replaces these with ancient ruins, which don't carry the risk of barbarian attack; instead, one possible bonus from exploring them is revealing the locations of several nearby barbarian camps.)
** In the ''Civ V'' expansion ''Brave New World'', Indonesia's unique unit is the Kris Swordsman, which gets a unique promotion at random after its first battle. While most of these promotions are very powerful, two of them, Enemy Blade and Evil Spirits, seriously diminish the unit's fighting power; the former causes it to take 20 damage if it ends the turn in enemy territory, while the latter gives it a 10% combat penalty when attacking and a 30% combat penalty when defending. The Ambition promotion is a double-edged sword, giving the unit a 50% combat bonus when attacking but a 20% combat penalty when defending.
* ''VideoGame/SidMeiersAlphaCentauri'' contains terrain features that are supposedly escape pods from the crashed starship. Could have personnel, could have recoverable tech data, could have a map of local metal deposits, could have [[FaceFullOfAlienWingWong helminthoid parasitic mindworms that attack your troops and psychically prey upon their minds before ripping apart their]] [[NightmareFuel AAAAAAA GET IT OFF MEEEE...]]

[[folder:Hack And Slash]]
* The various ''{{VideoGame/Gauntlet}}'' games have poison and Death hiding in treasure chests identical to food and potion chests. It's impossible to tell which is which without opening them. ''Gauntlet II'' had poisoned cider and poisoned blue potions. Shooting either of them would cause enemies to slow down. There was also "IT", which chased down a player and bonded to him or her, causing enemies to follow them. The IT effect persisted throughout the level and can only be mitigated by tagging another player ("Tag, you're IT!"), which simply passed the effect to that player.
** The upgraded ''Gauntlet: Legends'' and its sequel, ''Gauntlet: Dark Legacy'', avert this somewhat with the X-Ray Glasses power-up, which allow you to see what the chest contains; even without the Glasses, observant players will quickly notice that if a chest is shaking and jumping, it very likely contains Death. In any case, each chest location holds the same type of power-up every time, allowing the wise player to avoid opening harmful or useless chests on replay.
** ''Gauntlet: Dark Legacy'' had green apples (poison fruit that cost a player 50 health) and green drumsticks (poison meat costing 100 health). You could tell if food was poisoned if it was green, had two bones sticking out of it in an "X" and had a bite out of it. Good food (red apples and brown drumsticks) could become poisoned if it got hit with what came out of a green barrel (poison gas).

[[folder:Maze Game]]
* ''VideoGame/LadyBug'' had skulls scattered around the maze with the dots and other pickups. Running into a skull would lose a life for the player, but skulls were just as deadly to the enemies. There were more skulls on later levels than earlier ones.

[[folder:Miscellaneous Games]]
* In ''VideoGame/GirlsGarden'', picking up dead black flowers will kill half of the blossoms in Papri's bouquet. Also, the bee can drop a deadly skull.

* ''VideoGame/KingdomOfLoathing'' has a [[http://kol.coldfront.net/thekolwiki/index.php/Dungeons_of_Doom_potion series of potions]] that are a clear reference to these sorts of items. Their effects are mapped to specific potions differently for each person and each ascension, so they're risky until you've got them mapped out - especially if you hit the one that increases drunkenness while you're one point away from your limit (which makes you unable to continue adventuring) and have more than the rollover cap worth of adventures left.
** It also has "goofballs". It enhances your skills for a 10 turns, after which it penalizes your character by weakening him for the next 30 turns ("goofball withdrawal"). How do you cut the penalty short? Take more goofballs. And the price of the goofballs? First one's free. Subsequent ones ramp up in price by 1000 meat each time. And subsequent consumption also causes lost of stat to boot. The moral? DrugsAreBad.
** Food and booze of particularly low quality may reduce your stats upon consumption. Some may also harm you, and a few will actually poison you.
* Drugs in ''VideoGame/{{Achaea}}'' include cactus weed, gleam, alcohol and tobacco. Effects range from slurred speech and nausea to crippling withdrawal symptoms, distracting or disturbing hallucinations, and ''death from overdose''.
* ''VideoGame/WorldOfWarcraft'' has the [[http://www.wowhead.com/?quest=5253 Crystal of Zin-Malor]] that some players have actually found a use for (despite the fact it constantly damages you if you have it equipped) as opposed to turning it in for a quest.
** The alcoholic items actually get you drunk. Your screen becomes blurry, you sway to one side, and you see enemies as lower level than they actually are, [[FridgeBrilliance simulating the lack of fear that drunk people often have in dangerous situations.]]
* The laboratory maps in ''VideoGame/CityOfHeroes'' and ''VideoGame/CityOfVillains'' sometimes feature lab equipment, that when destroyed, will bestow a random temporary status change on you. It can be a good one (increased regeneration, recovery, recharge rate, damage) or a bad one (decreased regeneration, recovery, recharge rate, damage, or just damages you outright). As the duration is several minutes and the bad ones can be debilitating, many players don't take the risk and just leave them alone.
** The bad effects need to actually "hit" the player, while the good ones always hit, so increasing your Defense by any means before destroying a lab will allow you to get only positive effects, unless you are really unlucky. Also, the good effects last longer than the negative ones.
* In ''VideoGame/{{Runescape}}'', there is a classic scam of taking a special sort of fish (the ONLY kind you can cook half-way), and having you cook it. You might think that it is completely cooked, but it ''isn't'' (it's cooked ''half-way'', remember?), and eating it damages you for 30-50 HitPoints, maximum 99, ''and'' poisons you to the tune of ''13 HitPoints every ten seconds''. Needless to say, you are screwed if you eat it, especially if you're in the middle of nowhere. On top of that, the ''only'' hint of the fish's harmful effects is the description "This fish looks rather dodgy", but when you're low on health, the last thing on your mind would be to read the descriptions of every item you have. Finally, the fish is one of the few of its kind in-game, so there's no reason to assume it would kill you.
* ''VideoGame/FinalFantasyXI'' has several variations of poison potions and similar items. Using them afflicts you with a status debuff. More useful than you might think actually, because having a status effect already overrides you acquiring another of the same type, even if it is stronger. Even better, most types of Sleep are completely useless when you are Poisoned, because the DOT you have will immediately wake you up and help save you from a potentially more lethal attack.
* The Assassin Cross class in ''VideoGame/RagnarokOnline'' can, with a certain skill, mix bottles of Deadly Poison, drinking which will poison but also buff them, but a character of any other class will die on the spot when drinking this.
* ''VideoGame/DragonNest'' has rotten versions of food items that have a differently colored aura and a grey tint when compared to their originals. The penalty for each is ''at least'' a hefty 30% of a character's ''full'' HP or MP (sometimes ''both'') or a nasty debuff and it's hard to spot them in the inevitable carpet of loot unless the player turns item labels on.
* Angel's Tears in ''[[VideoGame/NexusWar Nexus Clash]]'' are fantastically useful for curing characters who have been poisoned or cursed by demonic magic...unless the character in question ''is'' a demon, in which case it horrifically burns them from the inside out instead.

[[folder:Party Game]]
* The ''VideoGame/MarioParty'' series used to have Black Stars (called Ztars in ''Mario Party 5'') which would reduce your number of stars. Bowser loves giving these out. Extra points if you actually paid for them.

[[folder:Platform Game]]
* The TropeNamer here is the Poison Mushroom from the ''SuperMarioBros'' series, a subtle PaletteSwap of the iconic Super Mushroom. They first appeared in the Japanese ''Super Mario Bros. 2'' (known in the United States and Europe as ''[[VideoGame/SuperMarioBrosTheLostLevels The Lost Levels]]''), where picking one up was the same as touching an enemy.
** The SNES release of ''The Lost Levels'' made the Poison Mushrooms a completely and totally unmistakable solid purple with a skull on the cap of the mushroom and gave them angry eyes. If you still picked one of these up, [[TooDumbToLive you deserved it]].
** Subsequent remake on the GameBoyColor, ''Super Mario Bros. Deluxe'', retained the skull cap.
** ''The Lost Levels'' also has backwards {{warp zone}}s.
** In many ''VideoGame/SuperMarioWorld'' {{ROM Hack}}s a level gimmick might be the green orbs that complete the level scattered about. However they will be placed in areas where touching them will [[KaizoTrap result in Mario falling off the screen]]. You either have to avoid them or use a item (P-switch) to block a gap to complete these levels.
** In ''VideoGame/SuperMario3DLand'', the Poison Mushroom returns in later levels, but to make up for it being an easily-identifiable purple, it will home in on Mario, making you have to actively avoid picking it up if you free it from its ? box.
** In ''VideoGame/SuperMarioMaker'', you can deliberately do this by sticking any enemy inside of an "?" block, and emerge out of the block when players hit it. They even make the sound effect of an item popping out when they do.
* Some of the earlier ''SonicTheHedgehog'' games had the "Eggman Monitor" (Robotnik) item, which acted like taking an attack from an enemy if its monitor was opened.
** Their first appearance was in the 2-Player mode in ''VideoGame/SonicTheHedgehog2''. Particularly evil given that the monitors in 2-Player mode don't display an icon representing what's in them until you open them[[hottip:*:merely showing static or question marks]], and that the number of items collected is included in each player's score. The only ways to know you're safe from them is to memorize where and what every item is, or turn on the "Teleport Only" option (so all monitors [[FreakyFridayFlip make Sonic and Tails switch places]]).
*** In Casino Night Zone, if you get three Eggmen/Robotnik on a slot machine, you lose [[strike:all your]] 100 rings.
** ''VideoGame/Sonic3AndKnuckles'' had the these first appear in Act 2 of the Hydrocity Zone, but they are easily missed. Later they appear in the [[SlippySlideyIceWorld Ice Cap]] zone, where they used the "obstacle" approach (and are frozen in a layer of breakable ice, building in a slight margin for safety).
** Hacking also reveals that Eggman Monitors existed in the coding for the first ''VideoGame/SonicTheHedgehog''. They aren't programmed to actually do anything if you hack one in and break it, but one can assume that they would have if they were actually implemented.
* ''ToejamAndEarl'' had these in two ways. First was the food that you could pick up to recover energy. Good food included bacon & eggs, cake, and fudge sundaes. Among this good food is bad food, like moldy cheese and fish bones (and a few which look innocuous at first, like the lettuce, which turns out to be old). These would cause you to LOSE energy. The game was also scattered with gift-wrapped presents -- their contents are at first a mystery, but opening a present (or consulting a [[BunnyEarsLawyer wise-man in a carrot suit]]) will identify all presents which have the same wrapping paper. The presents were mostly good, like weapons, 'vehicles', food and money. Others were not so nice -- instant death, bad food, a sleep spell, or the infamous Randomizer, which makes you start the identification process all over again.
* The poison potions in ''VideoGame/PrinceOfPersia1'' and ''VideoGame/PrinceOfPersia2'' looked almost exactly like the regular potions (they had blue bubbles instead of red -- a detail that could be difficult to make out in the console versions if you had a small TV, and easy to miss in general) but hurt you instead of restoring or increasing health.
** Both of the original games also had a green potion that flipped the screen and reversed your controls. To reverse the effect, you had to find the other potion of the same kind.
** The Super Nintendo version of the first game, in one of the all-new levels, had a room with two large potions: the typical [[HeartContainer life-upgrade potion]], and a potion that instantly killed you.
* The "Fat Head" power up from ''VideoGame/DynamiteHeaddy''. It's occasionally mixed in with other powers in a power-up box, and if you accidentally pick it up, Headdy gets stuck with an over-sized head that forces him to move slowly and prevents him from jumping for several seconds. Fortunately, you seldom encounter it in a location swarming with enemies, but on the other hand, it occurs in multiple boss battles.
* ''VideoGame/EarthwormJim 2'' had a weapon known as the Bubble Gun, which is ExactlyWhatItSaysOnTheTin: It shoots out ''soap bubbles''. Obviously, it's not even remotely useful in trying to defeat enemies. What raises this above a mere PowerupLetdown is that (at least in the Genesis version) there was no way to switch weapons, so you were stuck with the last weapon you picked up until it ran out of ammo. This was a minor annoyance in the first level, where you could just stop and use it up, but a death sentence in the last level, a foot race against Psy-Crow, where you needed a useful weapon to clear away obstacles so you could beat him to the checkpoints, and using up the ammo wasted valuable time you didn't have. Failing to do so resulted in him [[StalkedByTheBell closing the gate behind him]] and triggering an inescapable DeathTrap (If you were ''lucky'' - if you weren't, a glitch would prevent the DeathTrap from firing, leaving you to [[{{Unwinnable}} sit in the now-sealed room until you gave up and reset the system]]). And even in the versions where you ''could'' switch weapons, you usually got the bubble gun at the worst possible moment.
* ''Rastan'' also had poisoned potions, which were red fluid in triangular bottles, as opposed to the safe blue potions in round bottles. While it reduced your vitality by as much as 15%, a red potion also was worth 10,000 points.
* ''VideoGame/CrystalCaves'' has deadly green poison mushrooms appear in a number of levels. Pick one up, and it's a level restart, regardless of how much health you had left. Unfortunately, they're not the only mushrooms in the game which can be picked up (red ones are an actual powerup, and blue ones are worth a lot of points). Also, since it's a simple PlatformGame, by "picking up" we mean "touching" or even "brushing against ever so slightly".
* Late in ''VideoGame/Stinkoman20X6'', you find poison capsules. These deal 1 damage to you and look like a sickly green PaletteSwap of the power crunch capsules that restore full health.
* In the PlatformHell game ''Syobon Action'', you will die if you touch anything that looks like a ''SuperMarioBros'' powerup (not only the Poison Mushroom). On the one hand, this means you should take care not to hit certain blocks from underneath, because you'll need to jump on them when they don't have a lethal item sitting on them. On the other hand, some of the game's puzzles are solved by feeding these items to enemies.
* ''VideoGame/LegacyOfTheWizard'' had a poison item that was quite obvious, what with having a skull on it and everything. It would drain some of your life - not ''that'' big a deal unless you were badly damaged. The problem is that they're commonly dropped by enemies and can be difficult or impossible to avoid in narrow corridors, forcing you to wait for them to disappear. Graciously, you can walk past them, since the enemies have to [[DeathThrows plummet offscreen Mario-style]] before their spoils appear.
* The "Sleep" ability in ''VideoGame/{{Kirby}}'' is absolutely useless; it puts Kirby to sleep, without healing him, for approximately 5-10 seconds, leaving you vulnerable to any sort of enemy attacks.
** ''VideoGame/KirbySuperStar'' actually uses the ability as part of a challenge during "The Great Cave Offensive": one room has a number of Sleep powerup spots, a wind blowing towards the entrance, and a treasure at the far end. The trick is to get to the treasure without hitting a Sleep powerup, which will cause Kirby to fall asleep and be blown back to the entrance.
** The True Arena in ''Kirby Super Star Ultra'' always has a pedestal with the Sleep powerup and a pedestal with an actually useful ability, which combined with the 5 tomatoes that barely heal you instead of your precious Maxim Tomatoes just goes to show how NintendoHard The True Arena is.
** ''VideoGame/KirbySqueakSquad'' attempts to give Sleep a modicum of use: once you get the Copy Scroll for the ability, it will restore a small amount of health. Of course, you could just stock up food items in the touch-screen based inventory instead...
** There is also ''VideoGame/KirbyAirRide'', where hitting someone would put him asleep too. But you still need a very good luck to hit someone when you can't turn...
*** ''Air Ride's'' City trial mode had gray power up items, which reduce the stat they were for instead of raise it. There's also an event that made some power up items turn fake. These had a subtly changed sprite and cause a small amount of damage if you grabbed one.
* ''VideoGame/YoshisStory'' has the peppers, which are similar in size to the fruit your Yoshis need to eat in order to complete the game, and sometimes found in the same bubbles that fruit is often found in. Eating it damages any but the hidden Black and White Yoshis, and even the Black and White Yoshis don't count it as actual fruit (they're just immune to the damage, and it heals them a little.)
* Eggplants from ''VideoGame/WonderBoy'' and ''VideoGame/AdventureIsland''. Like all power-ups, they're hidden inside eggs, so you won't know you're about to open one up until after the ominous-sounding music plays. When you do, your health meter drains three times as fast, leading to a very quick death if you don't [[WizardNeedsFoodBadly eat up quickly.]] In ''WB'', the bad eggs are spotted, while in ''AI'', there is no distinction.
* In ''VideoGame/SuperMarisaLand'''s unlockable "Alice Mode", all of the mushrooms that previously served as power-ups now serve as {{Poison Mushroom}}s. ''All of them.'' You have to complete the ''entire game'' without powering up. At least you have the dolls to throw...
* In ''VideoGame/AlexKidd in Miracle World'', some blocks contain a GrimReaper that homes in on and kills you.
** Ignoring the "?" he spawns in will often shift him to another one later in the level. The one he shifts to if ignored normally contains a powerup or even an extra life, so it's in your best interests to "risk" him at the first opportunity and try to escape or glitch him out of existence.
* ''VideoGame/LowGMan'' has red potion bottles that drain one block of health instead of restoring one block as the blue potions do. In fact, the main attack of one of the stage bosses is to throw these bottles at you.
* ''VideoGame/NewSuperMarisaLand'' has the blue mushroom, which turns Marisa into a Yukkuri. In this form, she can very easily spin out of control, and whatever form she was in before is lost. Similarly, there's the UFO Suit, which is slow and reverts back to small Marisa after a short time. While these powerups have their uses, they more often than not exist to make life difficult for the player.
** The World 7 boss, [[spoiler: Nue Houjuu]], throws powerups at the player. The only problem is, you fight her in mid-air in UFO form, and all other forms will make Marisa plummet to her death. [[spoiler: It is entirely possible to catch a [[InvincibilityPowerUp Super Mushroom]] and fall into the boss, killing her in one hit. Good luck actually pulling it off, though...]]
* ''VideoGame/TheQuestOfKi'', like ''VideoGame/TheTowerOfDruaga'', had one type of item found in chests that would make the level timer run out faster.
* In ''VideoGame/{{Athena}}'', among the items that could randomly drop were flasks of poison which running into would cause Athena's hit points to start draining. This could be countered either before or after by picking up an antidote flask. The harp item, that would let Athena keep her items after dying, had an evil version that instantly took all of them away. In the NES version, the hourglass item that affected the timer also had a broken version that would reduce rather than increase it.
* ''VideoGame/KickMaster'' has a "poison" item that decreases your LifeMeter. It's utterly obvious and avoidable unless you're not looking closely at what enemies drop.
* In ''Ninja Jajamaru-kun'', breaking open the brick sections of platforms sometimes reveals useful powerups and sometimes bombs that kill you if you jump into them but go away after a few seconds. The sequel ''Jajamaru no Daibouken'' also has bombs in blocks, though these don't disappear on their own.
* ''VideoGame/Rockman4MinusInfinity'': The Skull Amulet (obtained by finishing off Skull Man with the Recycle Inhaler) originally cursed Hell Wheel (Skull Man's weapon), making it incredibly slow and turning it into an outright JokeWeapon. This was changed in the v0.01 release.
* ''Werewolf: The Last Warrior'' had a blue "W" which would cause you to be BroughtDownToNormal if you were a werewolf (the red "W" powerup effected the inverse transformation) or cause you damage if you were a human.
* In ''Fantasy World VideoGame/{{Dizzy}}'', it is possible to pick up a "large round hole". [[RedHerring It's not useful]]; as soon as you pick it up and store it in your bag, everything falls out through it. (Including the hole.)
* In ''VideoGame/{{Whizz}}'', enemies drop either red mushrooms that replenish the player's health or blue mushrooms that deplete it. What is insidious about this is that the red mushrooms will turn into blue ones if left alone. There is also a poison item that drains your health rapidly until you get to a first aid box; the final level actually forces poison on you.
* In ''VideoGame/TheKillingGameShow'', eliminating a group of enemies can spawn either a [[HeartsAreHealth heart that restores some energy]] or a skull that takes some away. These hearts and skulls float away in the same manner.
* ''Ironsword: VideoGame/WizardsAndWarriors II'' contains roast chickens that restore your health and swollen, bulging chickens that reduce it.

[[folder:Puzzle Game]]
* Pacman-like game ''Zoom!'' had a question mark powerup, which could randomly give you points, skip you to the next level, or kill you outright.
* The fairly unimportant '96 {{Breakout}} clone named ''Twinblok'' had a powerup that temporarily transformed all balls on the field into tennis balls. They turned completely harmless to blocks and the sudden change in their behavior was often lethal, since you were still obligated to keep at least one in play.
** Another Breakout clone called ''[=MacBrickout=]'' has blocks randomly drop capsules. The majority of the capsules do useful things, such as increase the size of the paddle, allow the ball to stick to the paddle, or giving the player extra balls to juggle. A few, however, would have negative effects, such as shrinking the paddle; the worst was the red "X" capsule which made the paddle useless. And getting too many "paddle expand" capsules would actually cause ''half of the paddle to break off'', so if you're close to the breaking point, even they prove to be Poison Mushrooms.
** This is common in Breakout-style games that use powerups. One variation, ''Alpha Bounce'', includes the "P" items that do something different depending on which paddle you're using.
** ''Breakline'' takes this to the level of a new artform. There are four types of ball, and passing over "+" and "-" squares will transform a ball into the next stronger or weaker type. Hollow spheres, the weakest type, can't damage blocks at all. Their ''main'' gameplay function is that certain blocks will emit hollow spheres, which you can control in addition to your main ball, aiming to guide them into collectors to receive in-game currency. Of course, if your main ball is "-"ed and then goes into a collector....
** ''[=BeeBop=] II'' had a block that took away your missiles, but had to be hit anyway along with all the other blocks.
* The objective of UsefulNotes/BBCMicro PuzzleGame ''Xor'' is to collect all the smiling masks. However, there are also frowning masks, which ''[[BlackoutBasement turn off the lights]]'', making the walls [[InvisibleBlock invisible]] until a second frowning mask is collected.
* The BreakingOut game ''VideoGame/{{Jardinains}}'' and its sequel have some bad powerups. If you know what they look like, you can usually avoid them unless they happen to be close to the ball at a crucial moment.
** Shrink Paddle and Fast Ball do exactly what you'd expect.
** The Paddle Scrambler, which only appears in the second game, [[InterfaceScrew reverses the controls of the paddle]].
** The appropriately named Very, Very Bad removes the effects of all good powerups, makes your paddle tiny and the balls super fast. Unless you have great reflexes and/or are very close to finishing the level, this might as well be a death sentence. At least it looks like a no parking sign, so you'll [[SchmuckBait probably]] be smart enough to try to avoid it.
* Matching Broken Heart tokens in ''VideoGame/{{Huniepop}}'' deals a significant amount of damage to your Affection meter. In the early game, you can survive a couple of them, but by the late game when you need 2,000+ Affection to win, a single Broken Heart match is usually reason enough to RageQuit. Not for nothing do a lot of the Date Gifts remove them from the grid.

[[folder:Real Time Strategy]]
* The freeware VideoGame/{{Worms}}-esque ''VideoGame/{{Liero}}'' features a weapon called the Booby Trap, which creates land mines disguised as medikits. They could be distinguished from the real thing because they didn't bounce like the real powerups did.
* ''VideoGame/CommandAndConquerRedAlert'' has crates that explode and cause damage when picked up.

* In {{Roguelike}} games like ''VideoGame/NetHack'' and ''VideoGame/DungeonCrawl'', what the different magic items look like varies from one game to the next.\\
Taking ''[=NetHack=]'' for example, in one game a square amulet is an Amulet of [[AutoRevive Lifesaving]], while in the next game a square amulet is a cursed [[ExactlyWhatItSaysOnTheTin Amulet of Strangulation]]. Part of mastering the game is developing tactics to discover which items are bad without killing yourself.
** ''[=NetHack=]'' also brings us the loadstone, an object which weighs an obscene amount (more than some characters' suits of armor) but if picked up cannot be dropped unless you cast an uncurse spell on it (and it automatically re-curses itself if you pick it up again). Of course, it looks just like two moderately useful other items when unidentified, and magical identification only works on items you're carrying... (Though [[spoiler: mercifully, a player can test unknown stones by kicking them; a loadstone won't move.)]]
** Several potions, even after being identified, can also be harmful if they are cursed, regardless of if you are aware of it or not. For example, potions of enlightenment usually give you insight and increase your wisdom, whereas cursed versions [[spoiler:just reduce your wisdom]]. Potions of gain level usually give you an extra experience level, cursed versions [[spoiler:warp you to the floor above you, that is, you gain a ''dungeon'' level.]]
** The Sink, Fountain, and Throne all have various effects when kicked/quaffed from, quaffed from, and sat upon respectively; most are beneficial, but negative effects are irritatingly common. In the upgrade ''VideoGame/SlashEM'', there are also Gypsies, who may cause anything from a free wish to instant death when talked to.
* PS2 Roguelike ''VideoGame/{{Baroque}}'' is full of these. You can be injured, killed, or otherwise negatively affected by certain items in your inventory, but in a more direct example of the trope, certain Meta-Beings will drop Disks upon being [[strike:killed]] purified. Disks that are visually indistinguishable from any other type of Disk. Disks that might, say, turn your sword into a piece of meat, or explode violently when stepped on. And by the time you encounter these enemies, you've probably gotten into the habit of instinctively picking up everything as soon as it hits the floor.
* The original ''VideoGame/{{Rogue}}'' had a Potion of Poison, a hallucinogenic potion, and the infamous [[InterfaceScrew "cloak of darkness"]] potion.
* In ''VideoGame/{{Angband}}'', the items which look different from game to game are rings, amulets, staffs, wands, rods, potions, [[MagicMushroom mushrooms]] (of course) and scrolls. All of these items exist in beneficial and harmful varieties. There are also cursed weapons and armor with negative bonuses; fortunately, ''Angband'' doesn't require the player to wield an item before identifying it. If you do wield a cursed item, it will instantly feel "deathly cold" and cannot be removed easily.
* ''VideoGame/PokemonMysteryDungeon: Explorers of Sky'' has the Lookalike items. The first one you'll likely come across (Or''e''n Berries) does the opposite of what it's supposed to do, but there are a few like the Slip Seed which are beneficial. However, the fact that you can throw items at enemies to forcefully apply their effect to them means even the bad items have their uses.
** Funniest of which is probably the Revi'''s'''er seed, which ''does'' revive the Pokémon... only for them to realize that there's an S instead of a V, upon which they faint again from bursting into spontaneous laughter.
* ''VideoGame/DungeonsOfDredmor'' has the "Potion of Replenishment" with the description that says it will replenish your health and mana. It also has the "Potion of Repunishment" with the description that says it will repunish your health and mana. The rest of the descriptions and image are identical.

[[folder:Role Playing Game]]
* In the ''StarOcean'' series, item creation often yields items like this, especially to begin with. One particularly annoying example is the Bounced Cheque in ''VideoGame/StarOceanTheSecondStory'', which continually drains your party's money until you get rid of it, which costs money to do since you can't throw items away and its sale value is negative.
* ''VideoGame/{{Fable}}'' also lets the player character drink, with approximately the same effect. He'll even throw up if he gets smashed enough.
* ''VideoGame/{{Faxanadu}}'' had vials of poison that looked very similar to health potions.
* ''VideoGame/PaperMario'' lets you equip some badges that have a negative effect on you, allowing you to make the game more challenging if you wish. Unlike the normal badges, they don't require any badge points.
** It and its sequel also had some recipe items that sometimes had adverse effects (such as negative status or damage). Additionally, in ''VideoGame/PaperMarioTheThousandYearDoor'', Mario could get 3 Poison Mushroom cards, which would give him an array of nasty effects.
* ''VideoGame/FinalFantasyXII'' had some equipment that gave godly stat boosts, but the trade off was forever status ailments (depending on what it caused) until you took the item off.
** These have been around in previous ''Franchise/FinalFantasy'' games. The ''Thorn Crown'' (found in 5 and 6) was a very strong headgear but caused a slow loss of {{Hit Point}}s, the ''Bone Mail'' (found in 5) was incredibly powerful armor but made you undead, [[ReviveKillsZombie which made magical healing hurt you instead]]. Another one was the sword Excalipoor (found in 5, used by a [[SummonMagic summon]] in 8) which made all your attacks do only one point of damage. And then there is the ''Cursed Shield'' (found in 6) which was very bad, but transformed into an incredibly good shield if you kept it equipped for 255 battles.
* ''VideoGame/FinalFantasyIX'' has the Tent, an item that normally restores the party's HP and MP to full when used at a save point or on the world map. Tents can also be used in battle for a single character, but there's a random chance that the character would be bit by a snake inside the tent, causing Poison. Blind, and Silence on them. However, [[ViolationOfCommonSense you can also use the Tent on enemies and hope they also get hit by the status ailments, including boss characters.]]
* A sidequest in ''VideoGame/LightningReturnsFinalFantasyXIII'' has you testing experimental potions for an alchemist, requiring Lightning to get herself afflicted with status effects. The second Nektar you're given not only fails to cure any status, ''it inflicts Slow on you''.
* In ''VideoGame/{{Mother 3}}'', there's an item called Fresh Milk that will restore 80 HP, but after only about a minute it turns into Spoiled Milk, which barely recovers anything. However, after about ten or fifteen minutes the Spoiled Milk will turn into Yogurt, restoring the 80 HP-recovery ability.
** Similarly, the game gives you Eggs, which are okay healing items. Hop into a hot spring with an egg and it becomes a Fried Egg, which is even better. But if you don't, Eggs will eventually hatch into useless Chicks, which grow up into useless Chickens (though at least Chickens can be sold for more than Eggs are worth.)
** Played for NightmareFuel on Tanetane Island in Chapter 7. [[spoiler:Upon arrival, a Save Frog alerts you that your party is in critical condition, and they are--everyone is down to 1 HP. Also, all of your items are gone. Only way to heal? Go a little bit into the island and eat some suspicious-looking mushrooms. The result? Your party is fully healed...but now [[MushroomSamba you're hallucinating like nobody's business]].]]
* ''VideoGame/BraveFencerMusashi'' features food items that spoil over time -- including milk that will go bad and then turn into yogurt. In this case, though, the yogurt is only about half as potent as the milk.
* In ''VideoGame/BaldursGate'' series, half the unidentified items are actually cursed items, a bottle that looks like a Potion of Mirror eyes (the protects from petrification) may instead turn you into stone, or an obviously magical sword is cursed to put the character in a permament Berserker state. Or the boots of double-speed, Faster then the speed-boots, but causes fatigue and renders the user unable to attack. However, the programmers unintentionally gave a way for savvy players to know what unidentified items are cursed (Hint: even Bards with High Lore can't identify them on the spot)
** Which is a continuation of the classical cursed items from ''TabletopGame/DungeonsAndDragons'' such as the Boots of Dancing, or a Dagger of Lycanthrope Sympathy (instead of killing Werewolves good, they're good at attracting them).
*** Classic cursed items in ''TabletopGame/DungeonsAndDragons'' also included weapons and armor that gave AC and to-hit-and-damage ''penalties'' instead of bonuses, such as a -1 sword or a suit of -2 armor. Naturally, once you equipped them, you couldn't take them off or otherwise be rid of them until a mage or cleric could cast a Remove Curse spell on you.
** The Vampire's Revenge sword from the first game is an especially nasty example. Not only is it cursed, it also does the exact opposite of what a sword is supposed to do. It drains its wielder's health and heals its target. Just to add insult to injury, getting the sword is a case of GuideDangIt which involves fighting a Doomguard, one of the most powerful non-boss enemies in the game, going through one of the most annoying dungeons in the game which is chock-full of respawning Kobold Commandoes packing fire arrows, and forgoing a valuable reward of 1500 exp. Pouring salt into the wound, the sword's flavor text ''mocks'' you for going through all of that trouble to get a piece of cursed junk like this.
*** ''[[HealingShiv At least you can heal your ally by swinging Vampire's Revenge toward them.]]''
** And who could forget the [[NightmareFuel Girdle of]] [[GenderBender Gender Change]]? Sadly the in-game effects of this were minimal.
* ''VideoGame/TheWorldEndsWithYou'' brings us the Red Skull pin, which slows down Neku's movement in battle. What the hell is the point of this pin, and why can't we sell it? Well, one mission revolves around [[spoiler:making this pin the next big thing, and to make it so you have to wear it in battle until the Gatito brand becomes #1 on the Scramble Crossing trend charts.]] And then plot-wise, this pin has a much worse effect: [[spoiler:during Kitaniji's [[{{Instrumentality}} super happy fun brainwashing time]], anyone wearing it but not the black Player Pin goes into [[MadnessMantra "To right the countless wrongs of our day"]] mode.]]
** It also has an unintentional amusing GoodBadBug use: by equipping it and then getting swarmed by tadpole enemies that also slow you down, Neku's speed loops around to negative, causing him moonwalk backwards away from where you point the stylus.
* In ''VideoGame/{{Ys}} Book I and II'', you find an Evil Ring in Darm Tower, which drains your health(or kills you instantly in non-TGCD versions) if you equip it and don't also have the Blue Necklace equipped. It is in fact required to rescue Lair later in the tower. Somewhat of a GuideDangIt.
** In ''Ys VI'', the Galba Armor inflicts [[UniversalPoison poison]] [[StandardStatusEffects status]] unless you equip the Silver Armlet first.
* ''VideoGame/{{Persona 3}}'' has the Cursed Cards in the post-battle Shuffle minigame. Sure, you get to keep whatever the Card yields like any other time... but [[TheGrimReaper Death]] is summoned to your side almost immediately.
** ''VideoGame/{{Persona 4}}'' has fake chests that, upon opening, "punch" you and drain your HP or SP. Pretty scary if you're not expecting it. These chests are not present in [[UpdatedRerelease the Vita remake]].
* The Black Potion in ''VideoGame/LightCrusader'' poisons your character, which in this game [[InterfaceScrew flip-flops the controls]] rather than draining health.
* In ''VideoGame/BatenKaitos: Eternal Wings and the Lost Ocean'', many item magnus undergo spoilage, resulting in what are usually very poor attack magnus. One particularly devious example, which you might not even see if you go straight to the end of the game as quickly as possible, is Yesterday's Wine. Deluxe Red Wine is a fairly decent healing item (though it gets outclassed later in the game), but after 24 hours (yes, of playing), it becomes Yesterday's Wine, which just gives you a Headache.
** Oh, and just for bonus points, you ''need' to get each and every one of these for HundredPercentCompletion. Be careful not to use them by mistake.
** However, items in Baten Kaitos can be used on both allies and enemies. This means that if your healing magnus spoils and turns harmful, you can simply use it on your enemies to damage them. Think of it as a card's purpose changing over time.
* ''VideoGame/GoldenSun'' has many items of cursed equipment; they are often quite powerful, but have the disadvantage that they cannot be removed without visiting a Sanctum, and may randomly cause the wearer to become paralyzed for the duration of a battle (although the latter effect can be mitigated by equipping a rare item).
* The chests left by defeated enemies in ''VideoGame/SecretOfMana'' may hold helpful supplies and other goodies. Then again they may only contain a booby trap, which can really mess you up. When you get a 'fake chest' which [[OneHitKill splatters]] the Girl and the Sprite and sends the Hero screaming like a little girl all the way to the nearest inn, you may decide to stop opening those things.
** There is a way to avoid this - the Identify spell (on the Girl's list of Jinn spells) disarms all traps. Of course, [[GuideDangIt it's only mentioned in one obscure spot]].
* A recurring trope in the ''DragonQuest'' series. Some weapons and armor the later half of the game found in chests are cursed. They usually appear quite powerful, but in reality, they give you lousy stats and cannot be unequipped unless you remove the curse. You can guess the item is cursed by its appearance and their description does warn you shouldn't try equipping it.
** The Cursed Belt and the Death Necklace from the first ''DragonQuest''. Being cursed by these adversely affects your stats and prevents you from returning to Tantegel until you see a certain guy in the nearby town to remove the curse.
*** Subverted In VideoGame/DragonQuestVIII [[spoiler: The protagonist can equip cursed items due to his Dragonian linage (Unaffected by curses except those of his own race)]]
* The {{Mac}} RPG ''VideoGame/TaskMaker'' has the Skeleton Scroll and Depressions scroll, both of which temporarily deplete some of the player's stats. Devil's Scroll even goes so far as to decrease the overall value of each stat.
* The [[IncredibleShrinkingMan Shrinking Potion]] in ''VideoGame/TheImmortal'' also poisons you, and you must find a cure after the shrinking effect wears off.
* Late in ''VideoGame/ChronoTrigger'', you can fight a rematch with [[QuirkyMinibossSquad Ozzie, Flea, and Slash]]. You can steal some decent equipment from Flea and Slash, but Ozzie yields the Ozzie Pants, which is inexplicably worn on your head. It provides great defense, but puts you in Confusion status at the start of every battle.
* The original ''VideoGame/{{Diablo}}'' had cursed armor, adding a bit of a gamble when you identified magical items. Cursed armor reduced attributes and didn't sell for much money.
* Consuming Datura root ([[TooDumbToLive if you're dumb enough]]) in ''VideoGame/FalloutNewVegas: Honest Hearts'' causes poison status for 30 seconds, which means you are screwed if you don't have Datura Antivenom.
* ''VideoGame/EccoTheDolphin'' has health-sapping clams disguised as healing clams.
* The ''VideoGame/{{Fallout 3}}'' DLC ''Mothership Zeta'' has the Alien Biogel, which restores 24 HP with the side effect of "Biochemical Anomalies"([[StandardStatusEffects random status effects]]). Elliot Tercorien can convert it into Adapted Biogel, which restores a lot more HP, but still has the side effects.
** In ''Broken Steel'', if you infected Project Purity with the Modified FEV, consuming Aqua Pura will cause stat debuffs and ultimately death.
* Due to the way Alchemy works in ''VideoGame/TheElderScrollsVSkyrim'', an inattentive player can ''[[HoistByHisOwnPetard make their own]]'' Poison Mushrooms. Alchemy ingredients have four effects each, and mixing them will make a potion which includes any effects which any two of the ingredients share with each other. If the ingredients share both a positive and negative effect (say, they both cause Restore Stamina and they both cause Damage Health) the potion will do ''both'' those things, but only be named after the most prominent effect, potentially producing a "Potion of Stamina" whose [[ReadTheFinePrint Small Print]] reminds you that it also drains your health. Fortunately, such potions make excellent VendorTrash, as their value increases with each effect, even if they cancel each other out.
* ''Franchise/{{Pokemon}}'' has several holdable items which do nothing but harm the user. However, they can actually be surprisingly useful if combined with the right strategy and Ability. The Flame Orb and Toxic Orb inflict burn and bad poison on the user, but they can be useful in combination with the Guts or Quick Feet Abilities, which require the user to suffer from a status ailment to take effect. Black Sludge hurts the holder each turn... unless it's a Poison-type, in which case it heals a little bit of HP each turn. The Iron Ball cuts the holder's Speed in half and if the holder is airborne it'll force the holder to the ground, but Gyro Ball (which becomes stronger if the user is slower) becomes more powerful and using Fling will deal a ''130''-base damage attack. The Ring Target removes immunities, the Sticky Barb damages holders but can transfer to those without items, and the Lagging Tail forces the holder to move last. The moves Trick and Switcheroo can be useful because it can transfer these items to those who really don't want them and hurt them.
* The Memoryhead in ''VideoGame/{{Undertale}}'' create a consumable called Bad Memory if you perform the "Item" Act option. It hurts for 1HP if used, although it fills up your HP if it's critical.

[[folder: Shoot Em Up ]]

* ''VideoGame/SoldnerX: Himmelssturmer'' has a bonus icon which instantly destroys your ship. In a game already NintendoHard and with sharply limited extra lives, [[FakeDifficulty its presence is most unwelcome.]]
* An old N64 game called ''Chopper Attack'', featured different bonuses if you blew up a certain base. These bonuses were random, sometimes giving health or ammo. Or other times it was a black box that jumped up and exploded in front of you.
* ''VideoGame/{{Parodius}}'' features an ''!?/OH ('''MY GOD''')!'' "powerup" on the power meter, which nullifies every powerup you have. Well, ''[[AllThereInTheManual ''It's hardly worth being called a power up'']]''.
** Normally, it's simple to avoid; just don't power up when it's highlighted. But throw in the "powerup roulette" feature that activates by random (though actually specific) power pods, and you'll see its [[ScrappyMechanic true purpose]].
*** Thankfully in [[UpdatedReRelease Jikkyo Oshaberi Parodius: Forever With Me]] featured an option to change the ''!?'' into a slot machine roulette, which not only reduces greatly the chances of getting that dreadful powerup, but also rewards you with upgraded versions of the bell powerups in the game, and also extra lives.
*** On more positive side, the [[GratuitousEnglish funny voiceover]] shouts the words '''[[OhCrap "OH MY GOD!!"]]''' loudly at Gokujyo Parodius, which truly shows the alarmed and frustrated feeling you get from that powerup. Sexy Parodius even gives every playable character their own shocked exclamations reacting to the selection of ''!?''-powerup.
* ''Warblade'' has a number of them:
** Skull powerups occur in red, green, and blue. They downgrade your weapon, as well as your speed, bullet count, and time stats. There are positive effects too, which lower the number of further bad powerups. The red, green, and blue varieties are all the same, except that if you collect a certain number you get a benefit:
*** Money thieves occur from time to time. If you get three blue ones, the money thieved explode into even more money when killed than they normally do.
*** Three green ones causes a multiplier to spawn at the beginning of meteorstorms, one of the more common bonus rounds.
*** Three red skulls will cause a gem counter to be added to the interface. you can make it permanent by playing 5000 levels total, though that may be overkill for such a minor detail.
*** A red, then green, then blue in order drastically upgrades your speed, and will also upgrade your weapon to super triple if it's lower than that.
** Far worse than skulls are weapon powerups, which can change your weapon to either single(you will lose if you pick up this one past level XX25(they cycle, every 100th level is the same but a bit faster)), double, triple(the normal kind, not super triple) or quadruple(this one's kind of rare, and doesn't suck so much). There isn't much of a problem on undeveloped accounts(in this game, achievements unlock significant, permanent bonuses) but on higher levels and/or highly developed accounts, this can suck because your weapons are far better than those. Heck, some achievements allow you to START OUT with quadruple or super triple.
** Less detrimental here, but if you pick up a money doubler if you have more than around 450000 dollars, you get red text saying "money doubler malfunction"
* Some shmups, such as SNK's ''Alpha Mission'', have "power down" items, in this game, the item's letter was reversed.
* The {{MSX}} version of ''VideoGame/TwinBee'' had a black bell that would kill you if you tried to collect it. Most later ''[=TwinBee=]'' games used the black bell as a Speed Down.
* ''VideoGame/KingsKnight'' had up arrows that acted as health restoration items. The landscape was also littered with down arrows, which ''decreased'' your life force, and grabbing one while your health was low would kill you.
* ''VideoGame/The3DBattlesOfWorldRunner'' had literal poison mushrooms. Items could be made to drop by bumping into columns, and mushrooms were the one bad kind of item.
* ''Battlemania''[=/=]''Trouble Shooter'' on the Genesis had a Speed Down item. They usually appeared in levels where slower speed was necessary for survival, though.
* In ''[[VideoGame/StarSoldier Star Parodier]]'', the powerups to avoid are the orbs with "suka" written on them.
* ''VideoGame/{{Enigmata}}'' has a number of them, marked with an "X" (except one). These usually cause InterfaceScrew such as money loss, taking damage, jamming your weapons or making you unable to move (or move in the opposite direction). Many of these can be negated/nullified with the right skills and equipment, and you can also decrease the chances of negative powerups occuring.
** The WORST one of these, however, is the "Bonus Killer", marked with a "Z". There's an item that makes your bonus weapons permanent, and a skill that locks your bonus weapon to avert PowerUpLetdown. The bonus killer on the other hand bypasses this- it turns your weapon back to the starting weapon, severely dampening your firepower. Worst of all, not even the negative effect nullifier will protect against it.

[[folder:Simulation Game]]
* In ''VideoGame/LostInBlue'', there are eight different kinds of mushrooms that you can find. Their effects differ from game to game; some will burn your throat and thus make your thirst meter go down faster, some will keep your energy meter from going down, some will induce stomachaches, and some will do nothing.

[[folder:Stealth Based Game]]
* In the original ''VideoGame/MetalGear'', [[DrugsAreBad the cigarettes kill you]].
** Unless you use them at the end of the game, which somehow increases the TimedMission timer.
** The snake that eats your rations in ''VideoGame/MetalGear2SolidSnake''.
** When you recover your inventory after being tortured in the first ''MGS'', it has a TimeBomb in it that you must discard before it explodes. Another bomb can be picked up while searching for the keycard in the drainage ditch.
*** This is a carryover from the original ''Metal Gear''. When you recovered your inventory after being captured then, a transponder is hidden in your equipment. Until you noticed and discarded it, enemies would be waiting for you at each new screen you entered.
* ''VideoGame/MetalGearSolid3SnakeEater'' has poisonous food items. These have one beneficial use: if The Fear is damaged enough, he will retreat from attacking you to find any Rations or Food around the battlefield, to heal himself. If you collect all of them and plant a Poisonous item, he will eat it without a second thought, further hurting his Stamina. Excellent for those trying to do Stamina-defeats on the bosses.
** [[MythologyGag Like the example in the original Metal Gear]], ''Snake Eater'' also had a tracking device get planted on you during the torture segment. Not removing it in the cure screen caused [[EliteMooks Ocelot Soldiers]] to show up while escaping along the riverside, but led to a [[EasterEgg bonus scene]].
* ''RiseOfTheKasai'' features an inversion of this trope. [[DarkActionGirl Tati]] can find literal poison mushroom pick ups and use them as weapons by planting them on the ground as mine traps for her enemies to step on, causing them to explode into a cloud of poison gas. It is played a bit straight though, as these mushrooms can prove lethal to the player and their AI partner, being the only player controlled weapon that can do so.

[[folder:Survival Horror]]
* The Whiskey in ''Videogame/AloneInTheDark2'' will mess you up big time if you drink it. Instead, you have to give it to a certain guy to obtain a Santa Suit, which is critical for entering the house without arousing suspicion (GuideDangIt).
** [[TomeOfEldritchLore "Fragments from the Book of Abdul" and "De Vermis Mysteriis"]] in [[Videogame/AloneInTheDark1992 the first game]]. The first book drains your health, the second kills you immediately [[spoiler:unless you read them while standing on a very specific spot in a secret room.]]
* The Rotten Egg in ''VideoGame/ResidentEvil5'' takes off a large amount of health, but [[LethalJokeItem throwing it]] deals a OneHitKill to Majini.
* In ''VideoGame/SilentHill4'', don't take the Shabby Doll from Walter, or it will cause extra hauntings in the apartment which block the ''item box'' and force you to waste your (limited) supply of Saint Medallions and Holy Candles to get rid of them.
* In ''VideoGame/SpookysHouseOfJumpScares'' the titular ghost "rewards" you with infinite stamina in Room 750, when what she actually does is disable your ability to run ([[ExactWords technically your stamina doesn't go down]]). It's unavoidable, but thankfully goes away after a few rooms.

[[folder:Third Person Shooter]]
* In the third-person shooter ''VideoGame/WildGuns'' there's the Mystery Power-Up (a bullet with a "?" next to it). While you can still get every gun in the game (Shot Gun, Grenade Gun and Machine Gun), woe onto you if you get the dreadful ''Pea Shooter'', which doesn't do ''any'' harm to your enemies and which you must discharge completely before you can switch back to your standard infinite-ammoed gun.

[[folder:Turn Based Strategy]]
* ''VideoGame/HeroesOfMightAndMagic 2'' had the Tax Lien (Makes you lose gold every day), the Hideous Mask (Monsters will never join you), and the Fizbin of Misfortune (Ruins your morale). You can see them on the map and avoid them, but sometimes you'd find them in treasure chests with no warning.
** The Fizbin is at least as old as ''VideoGame/MightAndMagic 3'' (not the "Heroes of" strategy series, but the apparently-lesser-known [=RPGs=]), where it doubled shop prices. It also eradicated you in the Slithercult Saloon if you had it in your inventory and tried one of the slot machines. However, with it you can take a treasure hoard you couldn't otherwise.
** Getting rid of a bad artifact in [=HOMM2=] was easy though. Just recruit a new hero, give him the artifacts and then dismiss him. (Removing him from the game). Did not work in HOMM I, though, giving you a message saying "this item can not be traded".
* Some of the relics your dwarf miners can find in ''DelveDeeper'' are "bogus" relics that are either either worthless or actually take points ''away''.
* The Devil's Axe in ''Franchise/FireEmblem'' tends to be this. Great stats, equippable by anyone with an Axe rank, good for training said Axe rank, [[BreadEggsMilkSquick and also has a random chance of damaging the]] ''[[BreadEggsMilkSquick wielder]]'' [[BreadEggsMilkSquick instead of the enemy]] (especially when the user was about to score a critical.) And since this is a series where FinalDeath is in play, most players wisely decide to treat the axe as VendorTrash instead of using it in combat.

[[folder:Wide Open Sandbox]]
* In the game ''WayOfTheSamurai 2'', the rice ball restores 200 HP, the ''rotten'' rice ball costs you 200 (it can't kill you, but it does come very unpleasant in the middle of a heated battle). The difference? Color and description, but who would read it in a battle? Furthermore, most thugs drop this and the real variety. The safer alternative is to just go for better health item, such as the (so-described non-perishable) dried fish, yum.
* ''VideoGame/{{Bully}}'' features a game-within-a-game called ''Consumo'', where the character attempts to become larger by eating the random food objects that fly across the screen. Eating rotten food objects such as spoiled rice, fish bones, or apple cores will cause the character to become sick and lose health or even lives.
* ''VideoGame/GrandTheftAutoViceCity'' allows you to take drugs (large floating discs similar to health pickups and bribes, except bearing an image of a pill), which temporarily slow you down until you get into a vehicle or go to a different area. In some cases, you might take corrosive damage and most likely die.
** These are in fact adrenaline pills. The "slowing down" is actually BulletTime, and during this you get super strength (just try punching someone and see what happens...)
** ''VideoGame/GrandTheftAutoIV'' allows you to get drunk, impairing your driving ability just like in real life.
* The 2005 remake of ''VideoGame/{{NARC}}'' also has a few somewhat useless drugs, Ludes reveals which persons are enemies and which ones aren't, another drug just zooms in and shows you close-ups of enemies for a few seconds, and Weed just slows you down, and your character will get addictions from all of them, though they're less severe than the addictions you get form the more useful drugs like Crack and Ecstasy.
* The racing game ''VideoGame/ReVolt'' has a "bomb" powerup; if you're unlucky enough to pick this up, your RC car turns black, its antenna becomes a fuse and it explodes after a few seconds (not destroying it, but sending it flying). Touching another car "gives" the bomb to them, though, so it's a lot like a game of "hot potato".
* You can buy drinks at the bar in ''VideoGame/RedDeadRedemption''. Virtually every other item you have to pay for is in some way beneficial--ammunition for your guns, medicine to recover health, apples for your horse, and so on. Booze? It gives no actual in game benefit (and the game never tells you this; it is all too glad to let you keep buying). It just makes you a slightly poorer drunk with [[InterfaceScrew no ability to walk a remotely straight line]]. You can blow $20 in one sitting on whiskey and then pass out in the street. Humorous, but a great way to wake up in jail.
* In ''VideoGame/RetroCityRampage'', drinking Milky's sour milk will cause the Player to get [[InterfaceScrew drunk]] and lose health. There is also a quack herbalist selling literal mushrooms with various harmful effects.

!!Non-video game examples:

[[folder:Card Games]]
* The ''TabletopGame/YuGiOh'' card game has "Parasite Paracide," which gets inserted into the opponent's deck, face-up. When they draw it, they take damage.
** Lava Golem and Volcanic Queen as well, both of them have high ATK and are played on your opponents field rather than yours, but inflict 1000 damage to the controller on their standby and end phase, respectively. They did have a plus-side for your opponent, though. Despite the negative effects, they are still 3000 ATK and 2500 ATK monsters respectively.
*** Similarly, there exists a monster call Ameba that causes 2000 points of damage if you use another card such as Creature Swap to give control of it to your opponent. There also is an equip card called Vengeful Servant that gives any monster equipped with it a similar effect. Even better is Number 30: Acid Golem of Destruction, which has 3000 attack and is extremely easy to summon but at the cost of only being able to attack for a few turns making you take 2000 damage per turn after that and making you unable special summon, so a good way to use it is to give control of it to the opponent with another card after the turns it can attack run out, making it play a similar role as Lava golem, but worse. Lava golem's main advantage over this is that you sacrifice your opponent's monsters to summon it instead of your own.
*** Ojama Trio and Nightmare Archfiends both give token monsters to you opponent that damage them when they are destroyed, and they can also block your opponent from summoning monsters by filling up all their monster zones.
** The Duston playstyle revolves around using "House Duston" to Special Summon members of the archetype to either side of the field, ideally Special Summoning ones with negative effects to your opponent's side of the field and ones with positive effects to your side of the field. This reflects how dust can spread in real life.
** Another excellent strategy that uses this trope centers around the cards [[http://yugioh.wikia.com/wiki/Nurse_Reficule_the_Fallen_One Nurse Reficule the Fallen One]] and [[http://yugioh.wikia.com/wiki/Bad_Reaction_to_Simochi Bad Reaction to Simochi]]. When either of these two cards are on your side of the field, any effect that would heal the opponent's life points will damage them instead, so you can pack your deck with cards that heal your opponent and use them to rapidly burn your opponent's life points.
* In ''TabletopGame/{{Fluxx}}'', some expansions (the first being ''Zombie Fluxx'') have "Creeper" cards. These are like the negative version of "Keeper" cards - they have to be immediately played, and they prevent the holder from winning the game even if they otherwise meet the conditions for winning (unless the goal specifically allows it or calls for a Creeper).
* The ''[[TabletopGame/{{Pokemon}} Pokémon Trading Card Game]]'' contains a promo card called Imakuni?, which confuses your active Pokémon upon use. That's all it does. The card itself was [[NoExportForYou only available in Japan]], but it also appears in the card game's video game adaptation.

* In the ''Literature/LoneWolf'' series of gamebooks, the hero can gather quite a few items; some useful, others not so much. And then there are the items that will make Lone Wolf's adventure harder down the line (or outright ''kill'' him) if he was dumb enough to pick them up. These items ''usually'' have very ''evil'' sounding names to warn the player that they're better off leaving them alone.
** The Glowing Crystal from ''The Caverns of Kalte'', [[spoiler:in fact a Doomstone. If Lone Wolf keeps it on his person for too long, its radiation will kill him.]]
** The golden bracelets worn by Ice Barbarians in the same book. [[spoiler:They are {{Hypno Trinket}}s allowing Vonotar to control them, and if Lone Wolf don one it can lead to a PsychicAssistedSuicide.]]
** The Black Crystal Cube from ''Shadow on the Sand''. It's not until later in the book that you learn [[spoiler:a) it attracts your enemies to your location, and b) it is going to explode in your hand if you don't throw it away fast enough]]. A similar one can be found in ''The Masters of Darkness'', and [[spoiler:if you keep it too long, it just kills you outright when exploding]].

* Aluminum in ''Literature/MistbornTheOriginalTrilogy''. Technically one of the sixteen Allomantic metals, but its only power is to erase all your other metal reserves upon burning.
** Also, burning an impure Allomantic metal will make you very sick, and trying to burn something that isn't an Allomantic metal at all will kill you.

[[folder:Tabletop Games]]
* ''TabletopGame/DungeonsAndDragons''
** Several campaigns feature poison found in a treasure haul, in addition to your regular potions. Characters that drank it suffered anything from hit point damage to outright death if they failed their saving throw.
** Classic cursed items in ''D&D'' include weapons and armor that gave AC and to-hit-and-damage ''penalties'' instead of bonuses, such as a -1 sword or a suit of -2 armor. Naturally, once you equipped them, you couldn't take them off or otherwise be rid of them until a mage or cleric could cast a Remove Curse, Dispel Evil or other such spell on you. Not to speak of the various other major cursed items you could run across (see ''VideoGame/BaldursGate'' above for more examples).
* ''TabletopGame/{{Monopoly}}''
** Any ''Chance'' or ''Community Centre'' cards that force you to pay money into the bank. The worst one of them is the "Assessment" card which forces you to pay money depending on how many houses or hotels you have.
** Any Chance card that forces you to move to a space (other than Jail or Go). Especially if said space is owned by someone else. And there is a Hotel on it. The "Boardwalk" card can be an especially fatal OneHitKill.
*** The Railway cards are even more annoying if someone owns all four. You have to pay double the rate, or $400, which is a large chunk of change.
** The ''Go To Jail'' cards play this straight early on, then is considered to be subverted later in the game (especially when houses and hotels come into play, as it delays the possibilities of you running into a fully developed property). Unless someone owns two of the three areas immediately after the Jail square (in which it is played straight again).
* In the 6th edition of ''TabletopGame/{{Warhammer 40000}}'', there were mysterious objectives which could contain a shield, AntiAir: They could also be ''booby trapped'', thus damaging your troops. Worse, these objectives could cause damage multiple times. There also were mysterious forests, which usually had fairly helpful effects, but they could also contain a nest of psychic-eating killer bugs which attacked absolutely every psychic model on the field. The Grey Knights, an army entirely composed of psychics, could reasonably count to lose half its troops just due to this one mishap. That's the reason why these things were removed in the next edition.

[[folder:Real Life]]
* There's a reason why many wilderness survival guides warn novices to think twice about eating wild plants and fungi. Best case scenario, a bout of horrible stomach illness and/or diarrhea. Worst case scenario, unwittingly ingesting a deadly poison. Examples of actual poison mushrooms that appear similar to edible mushrooms: [[http://en.wikipedia.org/wiki/Deathcap Death Cap]] and [[http://en.wikipedia.org/wiki/Destroying_angel Destroying Angel]]. [[note]]'''WARNING''': If that's not enough, these ''will'' kill you! By the time you get severe stomach cramps, [[ForegoneConclusion it's too late]] - in less than 5 days you will die of liver failure.[[/note]]
* TheOtherWiki has a list of deadly fungi [[http://en.wikipedia.org/wiki/List_of_deadly_fungi here]]. The [[{{pun}} morel]] of the story is: don't eat wild mushrooms, unless you happen to be an expert at identifying wild mushrooms.
* There are fish called Cleaner Wrasse that live in coral reefs. These fish are beneficial to other reef fish by picking parasites and dead skin off the bodies, thus the wrasse get a meal while the other fish get cleaned. However, there is another fish called the Sabre-toothed Blenny that mimics the coloring, body-shape and movements of the wrasse. Reef fish expecting to get cleaned by these fish end up getting a chunk of flesh bitten off by the blenny instead.
* The "caramel onion" prank. It looks like delicious caramel apple... but it's actually a nasty raw onion covered in caramel.
* People trapping food products and leaving them in innocuous places for fun, profit, or to teach a greedy roommate not to swipe their food. Imagine sitting down before a bowl of chili and discovering after a bite that it's full of dog food, or biting down into a brownie and later learning it was made with ''laxatives''. Other examples are the infamous Nair in the shampoo gag, lye in the socks, and even [[{{Squick}} a razor blade in the bar of soap]].