The wand of wonder has the ability to randomly cast any spell in the game, which is marginally useful in itself. However, it also instantly teaches the spell to your PC (just enough to cast it once or twice), even to classes that aren't supposed to be able to learn spells. You can cast from books without decreasing the spell marks; if you get lucky, find the right spellbook, and have enough power points, your mindcrafter can cast bolt spells.
There's also an item that is literally called "Potion of Uselessness" that does nothing when drunk, applied to items, etc. However, there is a level towards the end of the game with icy floors, and the only way to move around is by throwing items (to propel yourself in the opposite direction). Throwing the aforementioned useless potion to move yourself will result in your God rewarding you with one of the game's uber-powerful artifacts, with the on-screen messages:
*YE REALLY HAST FOUND A USE FOR THIS PETTY ITEM* * YER INGENUITY SHALL BE REWARDED*
In Assassins Creed II, the broom (or "Doom Broom", in some circles) acquired by bumping store owners holding them was treated as both a sword and a hammer for the purpose of counters. Since all of the counters but the ones that just knock the enemy down are 1-hit kills, the broom becomes laughably powerful. See that elite-looking guard in massive shining armor that dwarfs normal guards' armor? Let him strike at you and then counter, and if you are lucky (as in, not unlucky) you will hit them in the (armored) gut with the soft bristles and proceed to finish them off with an upswing that should merely give your enemy's helmet a dusting. Or, if you are really lucky, you will finish them off by slicing into their neck and pulling it out with a glorious spin. And yes, blood will fly if it is turned on.
The Fang in Backyard Baseball. It will always be a ball, but the batter will normally swing at it, resulting in a strike.
A pair of Golden Pantaloons can be found early in the first game, and have no obvious purpose. In the second game, one can also find the Silver Pantaloons and the Bronze Pantaloons as well. If you managed to get all three items, they can be used to create the most powerful armor as well as a couple weapons near the end of Throne of Bhaal, the last add-on. Overall the difference to standard equipment isn't that huge, though; the weapons especially aren't that useful.
In the second part of Baldur's Gate, you can also learn the spell "Limited Wish", which gives you (depending on your Wisdom) a number of dialogue options to be granted as wishes. If your wisdom score is really low, you may demand to be "protected from undead right now", which summons 6 hostile vampires. Combine this with the fact that evil clerics can control undead of lower level and you got yourself a free army of bloodsuckers (completely ignoring the Arbitrary Headcount Limit).
Somewhere approaching this trope lies another item. In Baldur's Gate 1 you can find "Arrows of Detonation" that explode into a 30-foot fireball when they hit something. In Throne of Bhaal you can find the Club of Detonation...very dangerous usually. Very useful if you've got over 100% fire resistance.
In Borderlands 2, players completing mission "The Bane" are awarded an SMG with the same name. Those who try it despite it's terrible stats will find it: a) reduces your movement speeds to a crawl when held, and b) the gun makes horrible screaming noises when it's fired and reloaded (even if you change the game's volume settings). Players who persist will find that the gun's stats are much better than listed, and it deals fantastic damage for an SMG — albeit at the cost of getting you kicked if you ever use it in multiplayer.
Unlockable only after reaching the highest level of Prestige, the MP44 in Call of Duty 4 Modern Warfare is both a Joke Weapon and a Call Back to the WW2 roots of the franchise. Players often disregard it as it can't accept any attachments and it lacks the accuracy of other weapons. However, it is one of the most powerful automatic weapons in the game. With the Stopping Power perk in place, it can kill even Jugs in three or four shots.
The key subweapon in Castlevania: Rondo of Blood and Castlevania: Dracula X is mainly for opening a few locked doors, but like all other subweapons, it has an Item Crash. The key's Item Crash looks silly (Richter or Maria rises into the air, then falls with a question mark over their head), but you're invulnerable during the animation and it costs zero hearts, so you can dodge attacks with ease. It also damages any enemies you directly touch while floating, and you float higher than a normal jump, so you can kill enemies on upper levels from below (again, for zero hearts).
Castlevania: Symphony of the Night has the Alucart equipment, which is basically joke copies of the true Alucard equipment. They give you poor stats and shouldn't be used — unless you use them all together, in which case your Luck is jacked up considerably (and your name in the status screen is Alucart!), making it much easier to get those random drops. Like the game-breaking Crissaegrim.
In Castlevania: Dawn of Sorrow, you have the Waiter Skeleton soul. It throws out a plate of curry that acts as a landmine, causing damage to any enemy that touches it. The damage is minimal, it's a pain to get, it only stays for a few seconds, and it's less of a hassle to just smash something than hope the enemy walks across it. Then you meet the Iron Golem and Final Guard, both of which move slowly and have titanic defense, and learn that a well-thrown plate of curry will hit them dozens of times, whittling their HP down far faster than almost any other weapon. It's also required to make the Yeti appear so that you can kill him and get his soul.
In Castlevania: Portrait of Ruin, there is a Cream Pie subweapon. It has an odd arc that goes forward and down. And does minimal damage. Unless you take the time to master it by constant use, which then gets it pretty powerful. It is also Dark-aligned, making Whip's Memory, normally a tricky boss, quite a lot easier, especially as the odd arc of the pie becomes just right for repeatedly hitting poor Richter in the face - and he is weak to the Dark element!
The game has a weapon called the Nemesis that works backwards — it's most powerful at level 1, but at max level it shoots rubber duckies. It only takes 1 XP per level to upgrade, meaning you now have to avoid all the bouncing energy crystals dropped by defeated enemies, or take damage to downgrade it.
There's also the Bubbler — at levels 1 and 2, it fires unimpressive bubbles, but when maxed out, the bubbles will build up as long as you hold down the trigger and turn into a swarm of straight projectiles when you let go, making it useful for taking down groups of enemies. And for hitting fast-moving or flying enemies. And for defending against projectiles. And for firing around corners. As the description says, "How you use it is up to you."
Crackdown had a joke weapon in the form of a rubber duck that could be thrown at enemies. Crackdown 2 made it lethal by turning it into the strongest grenade in the game. It's even better when you realize that its eyes glow red and it quacks.
And the sequel's Island King, the sword with the absolute highest attack stat (but lacking the combo speed of the Chronicle 2) is...a really sharp, ridiculous-looking Tiki mask with a pinwheel attached.
In Dark Souls II, the Handmaiden's Ladle is a weak and fragile "weapon". Its only advantage is that each attack with it has a very low stamina cost. Upgrading it to the Mundane type gives a fixed damage bonus to every attack that it won't lose if it breaks, so if all your stats are fairly high it is very capable of a Death of a Thousand Cuts.
The most useful weapon in Deadly Premonition is a guitar. Maybe it's because your villainous counterpart in the game is armed with an axe?
A big element of the game is using lethal joke items. For example, the King Salmon. Sure, it breaks after two hits, but that one hit does happen to do more damage than a katana. Not terribly useful when surrounded by zombies, but when there's one psychopath with a huge lifebar around...
Of course, there's also the "Real Mega Buster." It may look like the thing Mega Man wears on his arm, and it's even nearly identical visually to the ping-pong-ball shooters found in some of the mall's toy stores. But it's actually a very powerful arm-cannon that can take down even the toughest bosses in 3-5 hits, and it holds 300 energy rounds. Best of all, it respawns in the saferoom after running out of ammo. Good luck killing all those 53,594 zombies to unlock it!
The Hand Cannon in Dead Space 2 is a giant red foam finger worn over Isaac's right hand. It cannot be upgraded with power nodes and when "shot" Isaac yells out "Bang! Bang!" or "Pew! Pew! Pew!" depending on which mode of fire you use. It has no laser targeting like the other weapons and all in all seems like just a silly gag item, until you point it at a necromorph and "shoot" it, which causes instant death and severs every limb from said necromorph. It runs on infinite "ammo" and never needs to be reloaded, and shoots as fast as you can click your mouse. Unfortunately, you have to beat the game on Hardcore difficulty first, making it a Bragging Rights Reward as well.
Destroy The Godmodder: Although not a video game, it has many cases, including a broom capable of dealing damage to an omniscient being, and an extremely overleveled weapon that is... a fish wrapped up in a newspaper.
The original Diablo has a lethal joke spell called Flash. Not only is it a spell of ridiculously close range, it's also bugged — it does about 10% of its damage in three of the eight directions. It's also a spell of "magic" type, which is the most common immunity. However, the damage to CORRECT directions is unbelievable. Combine it with Teleport and you get TELEFLASH, one of the deadliest techniques against enemies not immune to magic. In the hands of a skilled player, of course.
Dragon Quest III features a Noh Mask, which has the highest defense power of any item in the game, but makes the wearer permanently confused and spending most of their time attacking the other members of the party; however, a solo character can essentially fight normally being confused, making this item invaluable for very hardcore or very desperate players.
Disgaea 3: Absence of Justice has quite a few "joke" weapons of varying usefulness. Probably the best is the Puppy Paw Stick, which grants a 20% chance to steal a random piece of equipment from each enemy the wielder defeats. This is especially useful in the Class World, where the player can randomly encounter duplicates of the party member hosting the world, wearing duplicates of that character's gear.
Disgaea 4: A Promise Unforgotten, on the other hand, made it harder to pull that trick off. To obtain the PPS, you have to catch a Basset (Tier Six Nekomata) and hope that the chest contains the stick. Mind you, getting the stick in the last game only required you to beat a fairly easy post-game boss. As for fighting the duplicates, they appear a lot less, given the new system for the Character World.
Dragon Age: Origins's DLC "Feastday Pranks" has the Butterfly Sword, with the special properties "Rainbow Power" and "Attracts Butterflies". It happens to be a decently powerful blade.
The Dragon Quest series; Naughty/Sexy Underwear, an "armor" item for the girls that appeared through some iterations of the series; although the joke is only in the nature of the item, its effects and atributes are generally great, making it a great equip. Also due to the blatant name, and its implication for the wearer venturing the land in nothing more than sexy lingerie, the item is widely referred in Fanarts and Doujinshi.
In Drakan: The Ancient Gates if you find and defeat a secret giant chicken you unlock the lethal joke weapon, The Chicken, which is...well...a rubber chicken that is tied for the most damage in the game.
Drakengard 2 has the Silver Butterfly, a relatively weak sword that becomes one of the most powerful weapons in the game (at least for the first play through) once you level it up. The sword itself is not entirely useless. Its low damage lets you rack up lots of combos if done right. The problem is that it requires about 4 times more XP to level up than most other weapons.
The several editions of Dungeons & Dragons have had quite a few of these intended as such. Honestly, in the hands of a creative thinker, damn near anything could qualify.
There's the "wand of wonder", an item that gives random effects when used — one charge might crisp a baddie with a fireball, the next might replace the user's hair with flowers. For many players, it was too unpredictable... until the 2nd Edition Tome of Magic introduced the "Wild Mage" class, which has a chance of controlling the wand.
The gray Bag of Tricks is an item that produces small animals that easily die, which can be used to distract a large group of guards and get them to leave their posts. Especially useful if combined with ghost sound to have the animal taunt the guards. It may not be a curb stomp, but it is using an item that is normally useless to high level players to get into a place without having to fight. Also, a stronger version of the Bag of Tricks has a chance of summoning rhinos or elephants — and there is no listed altitude limit as to where you can summon them.
Darts were usually given to mages for when they ran out of magic missiles. However, in 2nd ed, with weapon proficiency rules, a haste spell and gloves of returning, and +5 darts in each hand, a dart-specced warrior could unload enough damage in one round to kill gods (provided he didn't fumble — and he was critting on anything higher than a 2). Beware the dart warrior.
The Tree Token is a one-use item that creates a large oak tree on command. Combine with a flying broom and a sorcerer who's run out of spell slots in high seas combat, and watch the DM's face contort with rage/go slack with shock as you ask, "What's the damage on a caber?" 30' oak trees are also useful when you realise a creature is lurking on the 20' high ceiling of a room.
One D&D player reported in a comment on DM of the Rings#17 that an enchanted spoon that fills any vessel with gruel makes a decent dragonslaying tool. They had the cleric cast mud to stone until the dragon's cave was sealed, then made a small hole and stuck the spoon in it, drowning the dragon.
The Boots of Blinding Speed from The Elder Scrolls III: Morrowind. They do Exactly What It Says on the Tin — make you really fast, and blind you. However, Magicka resistance reduces or eliminates the Blinding effect, allowing you to move around very, very quickly without using Fast Travel. If you're a Vampire, these become absolutely essential, as the Fast Travel NPCs won't talk to you.
Skyrim's version of the Wabbajack nerfs the transformations and makes the enemies return to their original form after getting struck by an attack. But then there are now a whole slew of different effects it can take, including turning a target into a Daedric Lord and, although it is still your enemy, it will also become the enemy to creatures around it, causing them to fight against each other (probably while you start sniping them with arrows or magic). Then there are explosions and more explosions. Of course, they just had to add that chance of one-hitting that one boss.
The franchise in general has the Atronach Birthsign. At first it looks like a joke, gain the best magicka boost in return for losing your natural magicka regen. This, however is made up for by the fact that you also have a 50-50 chance of absorbing any spells cast at you (with the absorbtion giving you magicka back), making mages much more manageable. Take Alchemy and make a lot of magicka regen potions, and you eliminate the magicka stunt altogether, leaving you with a hefty 50% chance at spell absorbtion (a spell effect that is extremely rare to get outside of spells, if at all) and the best magicka boost in the game.
EverQuest has the Mossy Twig. It does very little damage and it initially seemed like a joke. Until someone figured out it was really, really fast. When you have spells or other items that go off every time you swing a weapon, it can be devastating.
Fallen London has the Ridiculous Hat, the Bottled Oblivion, and the Talkative Rattus Faber - all they do is take up an equipment slot and reduce your main stats, which would seem to make them joke items at best. However, due to the way the game works, the ideal Change-Points-per-action ratio is achieved with Chancy challenges - meaning that, if you want to level up quickly, you have to make sure that every challenge you take is Chancy. And just like that, the Ridiculous Hat goes from worse-than-useless to vital. (Also, the Boatman's Dynamic Difficulty is a step function. You want your Watchful to be exactly one less than the amount that causes him to scale up.)
The firsttwo games both have the Red Ryder Limited Edition BB gun, which has the same average damage as a sniper rifle with half the weight, a 50% faster fire rate, and a 100-round magazine. Its best use is putting someone's eye out (no coincidence, since it's a Shout-Out to A Christmas Story.)
In Fallout 2, there are the flares. They do 1 point of damage, and cost one Action Points to throw. But if you take the perk Living Anatomy, you do an additional 5 points of damage to any attack. These 5 points ignore armor. So with 10 AG, Action Boy (Insert Girl if you wish)*2, jet*2 and cookies*2, you can have 18 Action Points, allowing you to do 90 damage per round to any non robotic ennemy. Including the end boss.
Fallout 3 brings us the Dart Gun, which looks ridiculous considering a main part of its construction is a little toy car. It only does a small amount of damage due to its poison effect...and instantly cripples the target's legs, reducing their speed to a crawl. Make one and show it to your Deathclaw friends!
One should also note that the poison damage caused by this weapon completely ignores armor, meaning it's just as effective on a raider as a guy in full power armor.
Fallout 3 also has the Rock-It Launcher, which can launch Vendor Trash with enough force to gib a person. As all objects in the game are considered to be the same density by the physics engine, it means that you can fire a teddy bear at a raider's head and it'll pop that sucker clean off.
If you talk to "Biwwy" in Lamplight Caverns, he'll offer to give you a "Wazuh Wifle" for 500 caps. Seems ridiculous for something you probably already have multiple free versions of by that point, but then again you should also have an ungodly amount of money and a high enough Barter skill to get it for half price at that point as well. Turns out, it really is called "Wazer Wifle" in your inventory, and you can repair it using other Laser Rifles. But, as it turns out, it's not just a Laser Rifle with a gimmicky name, it also has a higher damage than the standard Laser Rifle. Combined with the Laser's faster rate of fire, it becomes a highly viable alternative to the Plasma Rifle.
Completing, Point Lookout's main quest line rewards you with the Microwave Emitter, which looks like the Mesmetron, but is much deadlier and bypasses armor as well.
Fallout: New Vegas introduces Euclid's C-Finder. Seems to be a useless thing that a kid was using as a toy raygun. Turns out it's the target spotter for the Archimedes II laser satellite. Lampshaded by your companion Veronica commenting it was lucky the safety was on if you decided to activate Archimedes II.
And then much like Fallout 1 and 2's Red Ryder, New Vegas has the Abilene Kid Limited Edition BB Gun. It shares most of its stats with the regular BB gun...except for the ability to do 70 points of damage with a critical hit. Take into account that the weapon is silent (the only silent weapons more powerful with a crit are sniper rifles), light weight, and has no Strength or Guns skill requirements to get maximum, that critical damage is not affected by weapon skill, and sneak attacks always being critical hits and you've got an amazing weapon for a Courier with high Sneak but low Guns skill.
In Far Cry 3, the Flare Gun seems like a useless weapon at first. It has a slow rate of fire, short range, and it's easy to set the area around you on fire with. However, it will set any vehicle in the game on fire in one shot, disabling it and turning it into a time bomb. It's also extremely effective against wild animals, either scaring them off or killing them.
In Final Fantasy IV, doing a sidequest gives you the reward of a Spoon. What do you do with it? Throw it! Apparently it's the best throwing item Edge has. Unfortunately the joke goes away in later versions where they "properly" rename it Knife. The fact that the game contains a spoon item and Edward can't equip it is a travesty.
The Lustful Lali-ho is just a joke item—it's basically a porno mag. In Final Fantasy IV The After Years, however, it's insanely valuable, since it can be traded in the final chapter for an item that permanently boosts MP by 50— the best such item in the game.
The Recurring Boss drops a sword at one point which he claims to be the legendary sword Excalibur; only it's actually the Excalipoor, which seems powerful on the stat screen but really only deals 1 damage per hit. This is lampshaded in the Boss Fight beforehand where he attempts to use it on you with about the same rate of effectiveness (none). However, since the "Always hits for 1 damage" routine is run after fight damage is calculated, Skills that use the attack value, like Blue Mage's Goblin Punch and Ninja's Throw, use the listed value. However, those would merely make the sword Not Completely Useless. The true value of this sword is that it "Always hits for 1 damage" when the "Fight" command is used; it never misses. Because Magic Sword skills enhance a weapon, with the strikes themselves inflicted with the "Fight" command, any magic sword spell that inflicts negative status will always affect the enemy without immunity to that specific status, including the few bosses that are not immune to instant death, petrification, or tension (warp). It is almost an essential item to low level runs. It is also useful for killing the game's Metal Slime, the Skull Eater, which is nigh invulnerable despite only having one HP, except against a sword that never misses and always does 1 damage.
The Chicken Knife becomes more and more powerful as your escape count increases (increasing by 1 ATK on each escape, maxing at ATK 127). Even though it usually causes you to automatically run away from battles, with a few tricks, or using it on inescapable battles, it can be a really strong weapon to use. On the other hand, the most powerful sword, the Brave sword (ATK 150), will decrease its ATK stat by 1 on each escape, thus normal players have almost no use for the Chicken Knife while low level run players will love it. While the Chicken Knife's maximum ATK is 23 points lower than its counterpart, your agility is calculated in addition to your strength when determining damage for knife-type weapons, making it actually stronger than the Brave Sword.
And as well, the Knife doesn't cause you to run when you use certain Job abilities (e.g. the Archer's 4x Attack), meaning with the right couple of abilities, your knife becomes the strongest and fastest weapon in the vanilla game. In the Bonus Dungeon, though, there are weapons that surpass it.
Final Fantasy VI has Imp equipment. Being Imped makes a character much weaker, and wearing Imp equipment does just about nothing, but by Their Powers Combined, a character may become near-godly. With enough grinding (all of the Imp equipment is randomly dropped), it's possible to go into the final boss battle with thirteen of fourteen characters (one character cannot equip anything except Relics) transformed into Imps, but bristling with awesome equipment. This arguably makes the last boss easier; while it locks your special skills, all characters (even weak fighters like Relm) can strike with Imp Halberds For Massive Damage. Though the amount of grinding required to do that would make the characters too strong to need the boost.
The Kraken Club has the absolutely pathetic damage rating of 11, and a fairly average delay rating, but the bonus effect of 'occasionally attacks 2 to 8 times' (per attack 'turn'). By occasionally, of course, they mean almost always. Combined with FFXI's Limit Break system, and the fact that it can be held in the off hand while using Dual Wield, this has the potential to be extremely powerful. To the point that it was discovered to be previously the only way to beat a previously nearly unbeatable boss Absolute virtue extremely quickly before it was fixed Of course, the way FFXI's Limit Break system works (long story short: Enemies get various Limit Breaks too, based on how many times they get hit) also means that it can be just as lethal to the person using it.
Hocho stands out. Passable stats for its level, completely useless at End Game, and a 1% drop rate or less on a rare Lottery Spawn Tonberry. It's a Katana that also increases your cooking skill. Yeah. And not by a trivial amount like +1—oh, no. It raises it by +3, the same value as all the other +cooking skill equipment combinednote Hocho is japanese for Kitchen Knife. The developers would have translated it into english, but since it's considered a Katana they left the japanese name..
Tactics' array of swords includes the "Nagrarock", a sword that is pathetic in power, will deal absurdly low damage when it hits, and every once in a while turns people into frogs. It also grants a huge movement bonus, so if you're into Dual Wielding...
A Japan-only God Roulette Skill in God Hand involves dropping a pan on your head for almost no reason. But it is one of the most used lethal joke items as it gives you an invincibility frame. When everything on DIE can kill in seconds, the god pan will ensure that you won't take damage that will kill you.
Hedgewars follows the steps made by Worms when it comes to ridiculous powerful weapons. Bazooka? Shotgun? Desert eagle? Pff. Watermelon, a piano, a colorful ball launcher, or a birthday cake, among others? Consider yourself dead!
The rubber chicken in Highlander: Last of the MacLeods for the Atari Jaguar CD. It has longer range and does twice as much damage as an actual sword, and is the only weapon in the game that's worth a damn.
The Amiga science fiction action game Hired Guns has a banana as one of the weapons that you can acquire. It's the most powerful weapon in the game.
In Blood Money, you can get a nailgun. Very inaccurate, can only hit at close range, deals almost no damage, and it has a pause between each shot. However, when you realize that a headshot with any ranged weapon is an instant kill, your huge-clipped weapon becomes useful if you hide behind a corner while under attack by a large swarm of guards.
In Hitman Contracts, you can get a cardboard tube that, when used properly, results in an instant kill on nearly any enemy. The weapon's description mentions that it was "crafted from the finest natural cardboard and honed to its maximum lethality".
Iji can acquire more powerful weapons, but the Banana Gun still packs an explosive punch- in the form of a rubber squeaky toy shaped like a banana. It is also the only weapon affected by gravity, and thus can be thrown from above.
In Kengo: Master of Bushido, the strongest "sword" with the longest reach is actually an oar. Though it doesn't have a Spirit move, because it's made of wood, you can use it instead of a bokken when facing another dojo. This is probably a Shout-Out to the sword saint Miyamoto Musashi's (in)famous duel versus his lifelong rival Sasaki Kojirou, in which (long story short) he used an oar and won. It's worth mentioning that Sasaki's katana is waaaay longer than normal katana.
When using the Mystery Gear, Xemnas has heart shaped light sabers, Xigbar has a trumpet (they make honking sounds when you reload), Xaldin has six sticks with dragons heads on them, Vexen has a snowflake-shaped shield with a snowman on it (and ice is his element), Lexaeus has a moai, Zexion has a white laptop, Saix has a cute bunny and spaceship claymore, Axel has two giant ninja stars, Demyx has a big broom, Luxord wields several four leaf clovers, Marluxia has a giant bent water lily with a long stem, Larxene has eight lightbulbs, and both Roxas and Xion have a very spiky key.
That keyblade, for instance, is absurdly fast.
When using the Casual Gear, Xemnas has a pair of fans (of the kind used for fanning flames), Xigbar uses blowdryers (with a whoosh during use and reload), Xaldin uses brooms, Vexen has a pot lid, Lexaeus uses a Piko-piko Hammer, Zexion carries a giant sandwich, Saix waves about a giant BANANA!, Axel is serving up pizza, Demyx is playing a giant tennis racket, Luxord plays with some CDs (to be specific, Final Fantasy XIII discs), Marluxia has a Disturbing Ladle, Larxene is throwing some dragonfly barrettes, and Roxas and Xion swing around an umbrella. (Now if only theirs had been a stick or wooden sword).
Roxas does use a stick for a single mission. It is entirely useless. As Xion puts it:
Xion: Roxas, that's a stick.
In Kingdom Hearts Birth By Sleep the prize for making all the flavors of ice cream is a Keyblade called "Sweetstack". Said Keyblade is made of ice cream, and looks absolutely ridiculous. It also has a 100% critical hit rate, making it one of the most powerful Keyblades in the game, although its critical hit damage multiplier is pretty low.
In Kirby's Adventure, you have the Ball ability. To the average player, it can be a pretty bad weapon as it greatly limits your movement and makes you really vulnerable, and basically of little more use than Sleep. However, it deals damage proportionate to Kirby's speed, and gives quite a lot of invincibility frames, meaning that Kirby can just bounce through most closed areas killing everything in its path, up to and including minibosses.
The Hi-Jump is almost completely useless as an attack and typically only handy for moving through levels. Except against bosses; Every boss goes down with ease except Meta-Knight, who forces you to use the Sword power against him.
In Land Of The Dead Road To Fiddlers Green, the kung-fu fists are so powerful(& fast firing) they are also a Game Breaker. After finding them in a closet in your murdered neighbor's house, the game becomes a breeze, even with mods that add several thousand zombies, or turn your character into a One-Hit-Point Wonder. After getting the kung-fu fists, the only difficult mission is "Heavy Gunner", because you are given a minigun and must use it instead of the kung-fu fists.
The Banana Peel Arrow in The Last Story is a gag item only used to play pranks on people in town or set up hilarious traps for the few human enemies you will face...or you can use them to disarm Zangurak, a feat that is otherwise possible only by attacking him en masse for several seconds or with a perfectly-timed counter-attack. Plus, the satisfaction of seeing the second-toFinal Boss fall on his rump has no equals.
The ornamental swords go from being Vendor Trash to this in a New Game+. The most valuable one (the Diamond Sword) has a power of 60, while by the end of the first playthrough you'll have weapons well over the four digits. Once the cap on enchantments is removed, it is one of the weapons that grows more in power with each new enchantments.
In The Legend of Zelda: Twilight Princess, the final Arena-style sword battle with Ganondorf can be made ridiculously easy by using your fishing rod as one of these. The fishing rod has no practical use in battle, since you normally use it only for fishing, but if you pull it out, Ganondorf will stand and stare at the line while you wave it around, completely oblivious to the fact that he SHOULD be fighting you. You then quickly whip out your sword and slash at him while he's caught unawares...rinse and repeat, because he never catches on.
This is in turn a reference to The Legend of Zelda: A Link to the Past, where you could deflect the dark wizard Agahnim's projectiles with the Master Sword...or the Butterfly Net, which was normally just used to catch insects and fairies in bottles. Later games had the bottles themselves do the catching, and deflecting.
Also in Ocarina of Time were Deku Sticks, they break in one hit, are only available as a child, and were only of use to light torches... they also had the little hidden stat of being as powerful as the Master Sword pre-breaking, able to take down most of the child bosses in one to two well timed Jump Attacks.
The Boomerang in general is a Lethal Joke Item in Link's Awakening. In most games it's only really capable of stunning enemies, hitting switches from range, or collecting out-of-reach items; other than bosses, minibosses, and a handful of other enemies, the Link's Awakening Boomerang will outright kill enemies with only one or two hits, and the ones who can't be killed by it are still stunned by it. The only things that are "easier" to defeat without the Boomerang are ones with gimmicky weaknesses (such as the Iron Mask, who is easier to defeat with the Hookshot since it removes the mask that makes it immune to front and side attacks).
In Seasons some Subrosians steal your Roc's Feather and leave you with an item called the Fool's Ore. All you can do with it is swing it like your sword, which does nothing. However, if you find an enemy to use it on, you can kill it in 1 hit. The only enemy, however, is the Fire Pokey (which you sometimes dig up), and you can't leave the area until you get the Roc's Feather back, which replaces the Fool's Ore.
Following this trend, in The Legend of Zelda: Skyward Sword the net you use for catching bugs will also distract Demise during the first half of the battle and not only does it deflect the projectiles he fires in the second half, it's the only way to do so—your shield can only block them and trying to use your sword just gets yourself electrified.
Just like in A Link to the Past, The Legend of Zelda: A Link Between Worlds also brings back the Bug Catching Net. Just like in said game, it can reflect the projectiles fired by one of the main villains. But probably not like in said game, the upgraded form actually makes for a fairly viable weapon to use against enemies, doing about the same amount of damage as the most powered up version of the Master Sword. So for someone with good timing, you end up with a fairly viable melee weapon despite it looking utterly ridiculous.
Magna Carta 2 has the 1000 Ton Hammer, a weapon for Argo. It is a massive black hammer with the words "1000 TON" written on it, with flying birds above it to slam down upon enemies.
Mario Kart Wii's Quacker is a plastic duck on wheels. It is very possible to beat the opposition using the Quacker in the 150cc and Mirror divisions.
A somewhat literal example of a lethal joke item is provided by the Humor program in the Mega Man Battle Network series, which does nothing but replace Mega Man's usual advice with extremely bad jokes when it's placed properly. However, starting from fourth game, if you intentionally glitch it, it instead has the highly beneficial in-battle effect of randomly causing his next attack to deal double damage.
Ever make "Junk" out of Item Crafting in Mega Man Zero 4? They're actually ingredients for the Junk Armor, a set of armor that makes him even more of a Glass Cannon and doubles all damage he deals and receives. There are also S-crystals, which are never used as Custom Chips either, but make two of them and bring them to your friend Hirondelle for two free Sub-tanks.
The Monkey Mask of Metal Gear Solid 3 can briefly fool the final boss into dropping their guard. Similarly, the Mask (although it's required for a brief section of the game) can do the same for another boss.
Metal Gear Solid 4 has the Tanegashima lead ball musket in a mildly futuristic game. But it has a 1 in 3 chance of creating a tornado in outdoor areas, and most of the game does take place in outdoor areas.
In Might and Magic VII a club called Mash adds 150 points to strength and can be used by anyone without needing a skill. Of course, it also drops intellect and personality to near-vegetable levels. Whether it's worth the price is your call. If you're not a caster...
With the anvil system in Minecraft, you can give any item and block powerful enchantments. Want to kill zombies with a block of dirt that has Sharpness V, Fire Aspect II, Looting III, and Knockback II? Go nuts!
There's also the anvil itself. While the setup is incredibly difficult, setting up a trap where a player or mob gets stuck in a pit they can't get out of, then having an anvil fall on them, does two full hearts of damage for each block height that it drops (reduced if the target is wearing a helmet). Combine with a dispenser for fun and profit.
Thrown snowballs do precisely jack diddly to most of the enemies in the game. Except Blazes, who take massive damage. And the frickin Ender Dragon.
The Casey Bat from EarthBound. Joke? It has a very low chance of hitting depending on the strength of the ememies & the number of party members. Lethal? When it does hit, it hits hard. (This is also a Shout-Out to the baseball poem, "Casey at the Bat"- Casey swings hard, but strikes out.) When the random encounter system checks if you auto-win, it checks your attack power. With the Casey bat, this is much higher than it ought to be, so the game will let you auto-win fights earlier than you would be able to otherwise.
The sequel Mother 3 brings us the Honey Shower. It covers the opponent in honey, and bees mob them. The bees don't do a whole lot of damage, but they're sometimes followed by a bear who does.
In Paladins Quest, aka Lennus, the Bib is one of the strongest body armors in the game.
If attained as soon as they become available through sidequests, the joke weapons and armor in Persona 3 are actually far more powerful than anything else you'll be getting for several levels - sadly, being 'joke items' the characters will still attempt to trade them out for non-joke weapons and armor that are only half as effective.
Elizabeth's requests in Persona 3 will occasionally net you items like the Toy Bow and Spiked Bat. They have no special abilities and look silly, but they have 100% accuracy and attack strength is about twice that of any other weapons you can get at the same time you can fulfill the requests. The only downside: your party members will occasionally insist on switching to other, less silly weapons if you have them in the inventory. Nothing stops you from making them switch back, though.
Even more, certain quests or treasure chests may yield the High-cut Armor/Battle Panties or adorable Meido uniforms. While the girls tell you these are awful to wear, they'll do it anyway. For the time you get them, they have insanely high defensive stats. Being able to defeat the forces of hell with a squad of Maids? Priceless.
Persona 4 continues the tradition. If you happen to get the highest scores on you test in school, your little cousin Nanako will make you a paper bracelet to show you her appreciation. Said bracelet boosts every single one of your stats when equipped, and by a not-insignificant amount, too. The Power of Love indeed.
Phantasy Star Online has Akiko's Frying Pan. While weak compared to the higher level rare weapons, it has a low enough attack power requirement that with the right equipment, a level 1 character can equip it. It also has the Samba Maracas (which work like machine guns) and a toy hammer. There are also several umbrellas and parasols, which are easily the most powerful multi-hit weapons female non-melee classes can equip.
The Akiko's Frying Pan card in Phantasy Star Online III, which has AP and TP equal to half that of the opponent you attack it with, is one of the best cards to use against That One Boss Pollux, whose AP grows every turn, and thus lets the pan do more damage.
Resident Evil 2 has the Flamethrower for Leon to use that is the same type that Chris gets in the previous game and is just as worthless against zombies, lickers and bosses, but it makes very quick work of Ivy monsters, who otherwise take loads of precious ammo to kill.
The Spark Shot that Claire receives is so laughably useless that you'll probably end up wasting it on zombies just to save handgun ammo. But if you hang onto it, it absolutely trashes William Birkin and the Tyrant T-103-Type.
Resident Evil 4 has the Flash Grenade, which is explicitly non-lethal, but can disorientate groups of enemies. However, the "plaga-headed" Ganados, normally much more lethal and durable, will die instantly if caught in the blast radius of the Flash Grenade.
Resident Evil 5 has the Rotten Egg that damages you if you try to consume it. However, if you throw the egg at enemies, it does massive damage to them and can kill them instantly if they're weak enough! Rotten Eggs are also worth a lot of money when you sell them. There are also electric rounds for the grenade launcher that are pitifully weak against Majini, but are great for stunning Reapers and exposing their vulnerable spots.
The knife was largely seen as useless in the franchise, as the player character would merely thrust it forward for a single, weak strike, and it used up valuable inventory space that needed to go towards firearms and ammunition. Code: Veronica turned its animation into a slash that registered multiple hits, and then 4 made it even more useful by having it be permanently equipped without sacrificing an item slot.
Resident Evil for the DS did the same knife thing, though kept the same attack.
Ragnarok Online has some joke weapons and armor (and hats, lots and lots of hats). For instance, panties and an undershirt are a good choice of armor for Archers and Thieves. Also a spear that's a friggin greek column. And more, many many more.... They're no worse than standard weapons or armor (sometimes better).
Rune Factory 2: Your most powerful weapon is...the watering can, fully leveled up. Not only does it hit for high-close range damage, when fully charged (which ostensibly just waters a wide area), anything weak against water caught in the Area of Effect will get crushed.
Rune Factory 3 practically has a joke armory: from the Dekash (a weaponized tuna) to dual-wielded soup ladles to a fancy parasol or stuffed animal as shields.
They feature a series of weapons called "The Sheepinator" or some such, that transmute enemies into cuddly farmyard animals. The BlackSheepinator in the second game did the same thing, plus making them explode.
There's also the tool The Groovitron, a disco ball that can cause any enemy nearby to start dancing. Including the bosses. Including the final boss. And while they're dancing, you're free to attack them with everything you have. Using this during the final boss battle in Tools Of Destruction will give you vital moments to switch weapons, pick up ammo and Nanotech, and all in all just unload destruction on him.
Perhaps unintentionally, the RPG Realmz includes a cursed Dagger -2. By glitch or cruel twist, it's actually the most powerful weapon in the game, capable of felling most enemies in a single hit.
Saints Row 2 brings the Pimp Slap, a giant foam middle finger. It's big, it's red, it's ostentatious...and it can knock your target into next week. It has so much impact force that anything (read: anyone) you hit with it will often cross the render threshold before landing.
In The Third...take your pick. A giant floppy purple dildo kills standard enemies in two hits. An Arm Buster-like weapon straight out of Mega Man that has infinite ammo and qualifies as an explosive. A tank that looks like it drove right out of an Atari game which...well, it's a tank. The Johnny Gatmobile whose giant head contains a flamethrower. What takes the cake are the Apoco-Fists. Just like the Pimp Slap, they look like giant mascot hands. Mascot hands that hit people so hard they gib.
In Sengoku Basara, you can obtain Joke Weapons if you beat a stage at the highest difficulty (like Yukimura's giant matches, Ieyasu's drills, etc). They are also the strongest weapons of the game.
In Shadow the Hedgehog, after hitting trees, they turn into long sticks. They seem useless until you realize they work exactly like swords, and can kill enemies.
Skies of Arcadia has the Tuna Cutlass for Vyse and the Swirlmarang for Aika. They're Joke Weapon rewards for beating a secret boss (in the GCN version) or downloadable extras (in the original DC version). The Tuna Cutlass, which is a giant fish with a gutting knife as the secondary sword, has extremely low accuracy, but devastatingly high attack. Most of the time it'll miss, but if it doesn't, watch out. What's more, Vyse's S-Moves count his weapon's attack stat, but ignore the accuracy stat. In other words, they won't miss. On the other hand, the Swirlmarang, which was a giant lollipop, had extremely low attack, but high accuracy, and a 100% chance of causing panic as long as the enemy wasn't immune to it.
Slash EM, a NetHack variant, contains a similar weapon: the Houchou, which is a spoon that can be thrown for instant kills. However, it breaks after use, possibly making it Too Awesome to Use.
All the Joke Weapons of Soul Calibur 2 can be lethal because they are unblockable. Link's Joke Weapon is the Butterfly Net, as a reference to the above stuff about his canonical games.
In Star Ocean The Last Hope, there's the Tri-Emblum. At first glance, it's like the Tri-Emblem, the best unmodified accessory in the game...except with 1/100 of the stats and none of the cool factors. However, it has a particular hidden stat whose worth doesn't become apparent until the post-game: A Synth limit of 8. This allows you to synthesize up to 8 other items onto it to beef up its power. The regular Tri-Emblem has a limit of only 3, but transfers 100% of its stats when synthing. If you synth some Tri-Emblems together, you can get one awesome one with 4x the stats. Or, you could synth 8 of them to a Tri-Emblum, getting an accessory with 8x the stats of a regular Tri-Emblem, three of the four awesome factors found on the Tri-Emblem, and best of all, able to be duplicated for the dirt cheap price of 1 Magical Clay, allowing you to outfit your whole party with them. What's not to love?
Star Trek: Klingon Academy features a flying saucer (as opposed to the ones the Federation uses) as an Easter Egg. It fires a Death Ray, and a Radioactive Cow Launcher. It sounds funny, but these weapons can tear through bigger ships in seconds, and the saucer has the maneuverability of a flitting fly.
In Strike Force Heroes 2, one class of items you can get as a Booby Prize from the slot machine (which usually some item of amusingly gross Vendor Trash) is a "dooty launcher" that does damage in the hundred-and-tens, slows down enemies, and makes a humorous fart noise when fired. The only downside is it can't use Gun Accessories.
In The Suffering there's a secret weapon which is...a chicken. Which shoots eggs. Which are one hit kills and pretty much cut whatever they hit to ribbons. The only drawback is that you aren't about to be finding eggs scattered across the haunted prison to replenish your ammo.
Likewise, in The Suffering 2 you can, through a convoluted series of hidden events, obtain a giant plastic cocktail sword that even has a giant olive attached to it. It acts as a melee weapon and does very high damage; unfortunately, it's not a one-hit-kill weapon, uses up a weapon slot, and melee combat with the later enemies in the game is kind of suicidal.
In the first Summon Night: Swordcraft Story, at roughly the halfway point of the game, you can craft a sword tech from the Craftlord of Sapphire, who is basically just messing with your character. The tech turns out to be a cooking ladle, with pretty much the stats you'd expect combat-wise - in other words, abysmal. However, by putting a Mystic Ore into it, you can imbue it with the Fire element...and increase its durability. Eight-fold. Bear in mind here that the goal of most boss battles is to break their weapon before they can do the same to your weapon, and that much of the challenge of this is that you might accidentally get their HP to 0 first - and again, the ladle has pathetically low Attack. It helps that the ladle maxes out its TEC at 255, where the overwhelming majority of weapons max out at 100 or less, and TEC increases your combo speed, and that the ladle increases your AGI by 10 on top of that. Wish your enemies luck in breaking out of your combos before their weapons are broken - they'll need it.
Another property of the ladle that makes it even more lethal is that it costs 1 Mystic Ore to imbue it with Fire, but melting the Hot Iron Ladle down into your forge gives you 2 Mystic Ores. The value of this cannot be overstated; Mystic Ores are ridiculously hard to come by in any decent quantity, and always extremely valuable. To the point where discovering the Hot Iron Ladle in the first place seems like Insane Troll Logic, since it requires using 1 Mystic Ore on a useless weapon.
The Quartz Charm, acquired by beating Culex, seems to do absolutely nothing...but, in actuality, it lets you start every battle with the "Attack Up" and "Defense Up" statuses (that you normally get from flowers and Geno Boosts), which double your attack and defense. It also protects against instant-death attacks. The Ghost Medal is similar, but only works for defense.
The Lazy Shell Armor greatly reduces attack power and speed (the joke), but gives you so much Defense (the lethality), that you become practically invincible. Now, who would want to be invincible, but so weak you couldn't hurt a fly? Toadstool, of course! She can solo Culex (and anything else for that matter) while wearing the Lazy Shell Armor. It just takes a very long time to do so.
Then there's the Frying Pan. Wait, hitting enemies over the head with a frying pan? It's also Toadstool's best weapon.
Super Robot Wars Alpha has Tem Ray's Circuit. When you put it on any mech, its stats will be drastically reduced, the plus side is that the mech will cost only 10 credits to repair (in other words, the part turns it into another BossBorot). If you want real menace, however, just put it on EVA-01 along with another part to lessen the penalty, then send Shinji on suicide attack. Paying only 10 instead of 40000, using Berserk EVA now sounds like practical strategy.
The Paper Fan deals very little damage but is really fast, doesn't allow your enemies to move (much; it IS possible to escape...most of the time) while you're hitting them and can be spammed. You can deal insane amounts of damage to your enemies to the point that throwing the fan once you're done can send them flying offscreen. And if your foe is foolish enough to try to shield, if you smash with the fan you break it instantly. Throwing the fan will also send an opponent straight upwards into the air, a property that very few attacks or items reliably have.
The Bumper does no damage (Unless you throw it right at someone.) but a lot of knockback. It's especially impressive when the damage ratio is turned up (resulting in more knockback for the same hits), where it can become a one-hit KO unless you're on a very large stage or there are a lot of obstacles in the way.
Bonsly qualifies, despite not being an actual "item". When you send it out of the Poké Ball, all it does is walk around, doing no damage whatsoever. If you pick it UP, however, and throw it, it does insane amounts of damage and can often KO at very low percentages.
Tales of Symphonia has an entire set of these. When you rebuild Luin past a certain point, the weapon shop goes from selling earlygame weapons to Lethal Joke Items including a plastic pink dagger, a pair of paper fans, a tambourine, a deck brush, a baseball bat, a bag full of money, and a squeaky toy hammer. These are only about three steps below the most powerful weapons in the game, but they still give you about +700 attack.
On top of that, the "bag full of money" actually doubles the amount of money you receive from Random Encounters, although by the time you've rebuilt Luin to that point, the only thing worth spending large amounts of money on is said weapons.
Tales of Graces is similar. In particular, Asbel's giraffe-sword is second only to his Infinity+1 Sword, which is obtained partway through the final dungeon.
Tales of Vesperia has a sidequest involving an eccentric inventor that ends up netting your party lots of useful goodies: the last part of the sidequest requires you to perform various tasks, like doing enough total damage during a single playthrough, fighting enough battles, carrying enough money and running away from enough battles. As a reward, you get a shinai, a piece of grilled chicken made out of metal, a cat-teasing toy, a measuring tape, Heihachi's head made out stone on a handle with 765 Kg printed on its forehead, a deck brush and a slingshot with a blade attached to it. They're still useful, since like in the above example, their attack strength is compareable to most other endgame weapons, and even if it wasn't, all of them still teach you unique skills you can't learn elsewhere. The cat teaser and the deck brush also have unique special attacks, the latter of which even has potential to do an easy infinite combo.
Tales of Xillia 2 also rewards you with a very silly looking weapon for each of the party members upon finishing certain sidequests (Examples include a pair of popguns and an omlette pan and spatula for Ludger, a giant paddle for Gaius, and an enormous grilled squid for Alvin). Similarly, they're just about the strongest weapons you have access to prior to beating the game, thanks to both their high attack power and special abilities, and in the case of the pan and spatula for Ludger, allow him to perform a special attack if he's wearing his chef costume.
Jarate is basically an ascended joke weapon, said weapon being a jar of the Sniper's own urine. But it is useful for extinguishing teammates on fire, shorting out Spy cloaking, subjecting enemies to mini-crits for the next minute or so, and forcing your enemies to accept a terrifying new existence where people do awful things to them all the time for no reason and dignity does not exist.
Spy: "I have been SHOWN who is the BOSS!"
The Heavy's fists. Not very useful against any enemy charging you with a gun, but sneak up onto a distracted enemy and taunt.
The Sticky Jumper is ostensibly a training version of the demoman's stock Sticky Bomb launcher that has more ammo, but does no damage or Knock Back to the demoman's enemies. Normally this would be of no use to a class focused on blowing up one's enemies. However, when paired to the Ullapool Caber, itself almost a Lethal Joke Item (being a WW2-style 'potato masher' grenade of the sort one would usually throw being used to smack people, turning the demoman into an Action Bomb), things like this happen. This is because in a previous iteration, the Sticky Jumper negated all self-inflicted explosive damage, including damage from one's own sticky bombs, grenades...and the Ullapool Caber. Because a single swing from the Caber can One-Hit Kill seven of the nine classes at their starting health, Valve understandably nerfed the Sticky Jumper back to the level of 'training equipment.' Player outcry appears to have gotten Valve to remove the 'take double damage' item penalties and brought the Sticky Jumper back to Lethal Joke status.
Pyro's other melee weapons. (Aside from his stock and milestone ones.) A car battery, a rake, a mailbox, a lollopop and a sharpened volcano fragment.
Similarly to the Sticky Jumper is the Rocket Jumper; a Counterpart training weapon for the Soldier. Like the Sticky Jumper, it negated all explosive damage. However, one of the taunts you could do made the Soldier grab a grenade, pull the pin and blow himself up along with everything in the immediate vicinity. Normally, soldiers are loud and easy to spot, so it would be really hard to actually catch anyone in this (especially since they can just shoot your face in). However, with the Rocket Jumper, not only could you maneuver to the back lines extremely quickly and without drawing attention (you can jump extremely high without worrying about self-damage, and no one ever looks that high up), you also didn't die from your own suicide attack! This is especially potent against snipers and engineers setting up their sentries, as they will be completely vulnerable and unaware you're there and will generally be unmoving. Sadly this has since been removed from the game.
Another combination with the Rocket Jumper is a variant with the Market Gardener. The Market Gardener deals crits if you use it against someone while rocket jumping. This by definition means your feet must be off the ground for more than a split second. As the Rocket Jumper gave you "free" rocket jumps without hurting you, this made it the ideal pairing to the Market Gardener. Next up however are two items that takes this from "joke combination" to "lethal": The Mantreads and the B.A.S.E. Jumper. The Mantreads deal 3X fall damage to whoever you land on, if you would take fall damage. Since the Rocket Jumper lets you jump extremely high, most people use this to "cover" all their bases; they either whack the victim with the Market Bardener or stomp on them with the Mantreads. The other one is the B.A.S.E. Jumper, which lets you prolong your jump by slowing your fall. This, with correct timing, completely negates fall damage (as deploying it a split second before touching the ground slows you down enough) but also because of what defines a "rocket jumping" strike, it also means you can slow yourself down and continually smack the same person for multiple rounds of crits. Players would often find a way to jump as high as possible and deploy the Base Jumper and then glide about until they see a target, at which point they immediately drop down and re-open the B.A.S.E. Jumper, smacking the poor sod into oblivion.
The Holiday Punch is a literal Lethal Joke Item. Whoever is punched by them at the back would be forced into a 5-second taunt, consisting of them laughing their virtual asses off and being completely immobile. The weapon itself is paired with the (lethal) Showdown Taunt, which also comes with the default fists, which instantly kills anyone standing in front of the Heavy. Normally this taunt would be hard to pull off considering it takes exactly 5 seconds to execute...
Scout's Home Run taunt, using the Sandman and Atomizer. Line up your opponent, taunt and...
You'd think the Monkey Gun from Future Perfect would be a simple joke item - like hell it is. It has slightly limited use in that if you fire it, you have to use up the full 64 round magazine in one go (your limit is 4 mags total), but it gets rid of those in a fraction of a second, and just one of those rounds can be lethal. This makes it an excellent weapon if you're cornered by mooks.
On a similar note, the Mag Charger on the same game is pretty useless - until you realize that it can both see AND fire through literally ANY scenery on the game. It doesn't do a huge heap of damage, but it's accurate, fires quite rapidly, and anyone on the entire map is a viable target, even if you're completely hidden. Just have a back up for if someone gets too close, because it's no good in close quarters.
The Hoe of Destruction. Let all foes fear the power of your gardening tool!
Dirty diapers. Applying a dirty diaper upon an enemy would instantly rout him, thus making even nasty spellcasters easy pickings.
a number of the most powerful weapons and armor in Ultima Underworld 2 look exactly like some of the weakest. Examples: the Axe of Smiting (a hatchet), a cudgel that opens all doors, and a leather vest that makes you immune to fire.
Warriors Orochi 3 has numerous joke weapons as special weapons for many characters, including wrenches for Guan Suo in place of his normal nunchaku, a ruler (Called Measure of a Man) for Mitsuhide Akechi instead of a katana, and "poisoned dumplings" for Da Ji, a character that uses giant floating orbs as her weapon of choice. All of these have base attack damage just above the character's default weapon, but as the character uses them, many of these joke weapons will become more powerful then the normally ultimate fourth weapons. Only about three characters out of a hundred and thirty two are exceptions to this rule.
The Squeaky Hammer in Water Warfare. It slows you down, has no range and temporarily replaces your water gun, and, when used on people, simply stuns them briefly...except during those rare instances where it acts as an instant KO. It also grants invincibility, at least.
The Boots of Force from Wizards And Warriors. Why on earth would you want a short-ranged and awkward kicking ability when there are flashy projectile weapons you could get in that slot? First of all it damages everything, even the otherwise unkillable enemies. Secondly it does more damage than anything else in the game, including a guaranteed three HP of damage to any boss when most weapons do 1/2 HP at best. Finally, you can kick open chests that you don't have the key for.
World of Warcraft has the carrot on a stick. It's a carrot on a stick. You get it for defeating a three-headed hydra in a giant ruined troll city that takes at least 45 minutes (back in the days, that was already an incredibly short time for a dungeon) to finish if you're going for the hydra part ASAP. That's right, you go into an ancient troll city to defeat a mystical three-headed hydra and all you get is a carrot tied to a stick with a piece of string; no, it's not something the hydra drops, it's a reward from a NPC who wants the hydra dead. It increases your mount's movement speed by 3%, which seems measly, but being the only way to increase it at the time made it a powerful item for catching up with fleeing enemies, often deciding the outcome of a Pv P battle. In the current game, it's not effective for players above lvl 70, where faster mounts are available, which would make the item even more powerful. Instead, new items are available that can increase mount speed by up to 10%.
Another World of Warcraft item that has a surprise is the Last Relic of Argus, an item made through Archaeology. It's got a random teleport effect that sends you who-knows-where, but its secret value is that the teleport spell takes only three seconds to cast, where the usual methods of teleport take ten seconds on average, making it a very effective escape hatch.
During the initial parts of Wrath of the Lich King, due to feral druids melee damage being unconnected to the DPS of the weapon they had equipped and so solely based on the base stats... The best weapon in the game for them that wasn't from a high end raid boss, was a fishing pole.
Many of Worms 's sillier items fall under this trope. In fact, you could say that Worms' entire reason for being is this trope. There's homing pigeons, exploding bananas, skunks, concrete donkeys, exploding grandmas... And on the less ridiculous, Cherry Tapping an opponent with a Prod and making them fall into a mine or water is pretty funny, too.
In Xenoblade, defeating the Bonus Boss of a long sidequest arc rewards with two weapons for Riki. One of them looks like an oversized half-eaten fish, and it just so happens to be one of Riki's best weapons. This in contrast with the other weapon: A Joke Item with an impressive damage range of 1-1.
Yu-Gi-Oh! has Broken Bamboo Sword. Ordinarily, Equip Spells either boost the monster's ATK or give it an ability (for your cards) or lower the monster's ATK or impose a restriction (for your opponent's). Broken Bamboo Sword, meanwhile, increases the equipped monster's ATK by 0 and does nothing else, which means it does nothing but fill up the field, right? Well, actually, it has three support cards, all of which are game-changers. Golden Bamboo Sword lets you draw two cards, while Soul-Absorbing Bamboo Sword forces your opponent to skip their draw if the equipped card does damage, and Ghastly Bamboo Sword lets the equipped card attack directly, so long as you send a Bamboo Sword back to your hand (which makes it easy to recycle Soul-Absorbing Bamboo Sword). Basically, if you have Broken Bamboo Sword, you can duplicate the effects of Pot of Greed and Yata-Garasu, two of the strongest cards in the game.