All There in the Manual: The Gatherer Web site includes all rulings on cards. As the game goes on and rules get refined, the company almost constantly changes the way game abilities are printed on cards:
Every set introduces new rules terms and longstanding parts of the game may have their names or the related rules changed if necessary. The concept of the "exile" zone, for example, has been in the game since the very first set, but did not receive its current name until 2009. (Exiling cards is a way of removing them from play that's more final than most methods. It used to be called "removed from the game" but was renamed, partly because so many design ideas wanted to interact with cards that had been exiled or be used while the card itself was exiled, so "removed from the game" seemed more and more inaccurate.)
The general rule is to rely on the most recent printed text of a card to determine what it does, even if someone is playing with an older copy on which its abilities are phrased differently. Without that rule, for example, casting three versionsof exactlythe same card would mean none of them could actually attack.note This is because the first card prevents every creature type but Evil Eyes attacking. The second is a Horror, not an Evil Eye, so it can't attack. It says only cards called Evil Eye of Orms-By-Gore can attack (though it could potentially be read as saying only it can attack). The first card is called Evil Eye of Orms-By-Gore, so it can still attack. But wait! The third card says only "Eyes" can attack. The first isn't an Eye, it's an Evil Eye, and the third isn't an Evil Eye, it's an Eye. Therefore, none of the three can now attack.
Subverted by the joke cardR&D's Secret Lair, which explicitly bans using later printed text, errata or the rules to 'update' cards. It's, naturally, illegal in all competitive play, and rapidly makes friendly games very unfriendly.
The art for the cards has evolved over the years due to both a preference for more detailed, elaborate art, and much more meticulous guidance given to the artists. For example, when the company commissioned the art for the card Lord of the Pit, they reportedly gave the artist a one-word instruction: "balrog". (This was years before the Lord of the Rings movies were made.) Under the circumstances, it came out pretty well, but today artists get multi-paragraph descriptions of what the image on the card should look like, generally designed taking into account both exactly what the card itself does and the flavor and description of the world of the current set. Nowadays comprehensive style guides and concept art are made for each set, or consecutive block of set that share the same setting: for example, the goblins of the Scars of Mirrodin block have a large round head with a sharp snout and long pointed ears.
The cards' frames themselves have been updated. All frames have become less blocky and are no longer of an equal width all the way around, and the texturing used in each has been changed.
Even the "new" borders released in 2003 have changed. For example, the borders used for Artifacts in 8th Edition and Mirrodin proved too difficult to tell apart from white cards at a glance, and were darkened for Darksteel in 2004. Subtle tapering was added to two-color multicolor cards for Ravnica: City of Guilds in 2006 (although, in fairness, only one two-color gold card had existed in the new frames before that) to show which colors were involved.
The first colored artifact in the game was Transguild Courier, from Ravnica, which was printed on the normal 3-or-more-color gold card frame. Future colored artifacts, starting with Sarcomite Myr from Future Sight (which is the first artifact to be colored by actually having colored mana in its cost), introduced a new colored artifact frame that combined the outer frame of an ordinary artifact with a colored inner frame. The first card to use this in the normal modern card frame was Reaper King from Shadowmoor. (Sarcomite Myr was a timeshifted card on a "futuristic" card frame; by the time it was reprinted on the modern card frame in Planechase, the colored artifact frame had made its proper debut in Shadowmoor and, more extensively, in Shards of Alara.)
In addition, white card frames (previously used to distinguish core sets from Expert-level block expansions) have been entirely discontinued.
On the back of every Magic card that will ever be printed note not counting the double-faced cards which were released starting in 2011, players will find the word "Deckmaster." The Deckmaster brand ceased to exist in the mid '90s, but because every card has to be indistinguishable from the back, Wizards has to keep printing it.
The word Magic itself; on the back of the card, the word 'Magic' is (and always will be) blue, despite the fact that the official logo has been yellow for years.
Many card abilities. When the game was new, colors were very ill-defined. Many cards were placed in colors based only on where the creature in question lives or what it does, even if its abilities as a card are completely different from most cards of that color, but cards like that remain in that color now just because of the earlier ones. Look at a list of cards from most sets and compare it to descriptions of the colors and you'll always find a few cards that don't fit the description, but they're there because they are similar or identical to really common or famous or powerful cards that were printed back when the company was still figuring this stuff out.
The Gatherer text for Winter Orb returned to it an old, old rule; in old editions of Magic, any Artifact could be tapped to "switch off" its effects, a rule intended to emphasise their status as sorcerous machines.note Or at least it did, until, in true Wizards fashion, the Oracle wording was changed to reflect more recent behavior for artifacts. Now Wnter Orb no longer shuts off when tapped.
Templating changes have made some older cards counterintuitive. For example, when the card "Auramancer" was printed in 2001, the word "aura" was often used to refer to enchantments. In 8th Edition, local enchantments were re-templated to use the subtype, "Aura." This has caused a lot of confusion in more recent printings, since Auramancer can interact with any Enchantment, not just Auras.
Artificial Stupidity: The AI in Duels Of The Planeswalkers generally knows what to do with each of the decks, excepting a few mistakes it'll consistently make. However, in 2013 it has no idea what to do with the Plane cards in Planechase. It'll throw mana at rolling the planar die even when a success won't actually do anything, or when the current plane favors their deck, or when it really ought to attack before doing so, or in a few cases when a success would be actively detrimental (say, bringing them closer to death by milling).
The "Regenerate" mechanic allows you to create a one-time shield that prevents your guy from being destroyed, tapping it instead.
Lich's Mirror allows you to start the game over with 20 life if you die with it in play. Of course, you start over with nothing in play, but your opponent gets to keep all the cards they already have out.
Shadowmoor block had Persist, and Innistrad has Undying, both of which are abilities that return dying creatures to play with a counter on it (-1/-1 and +1/+1 respectively), if it didn't already have one.
Awesome but Impractical: Many cards have spectacular, awe-inspiring effects that will almost certainly win you the game - if you ever get enough mana to actually cast them before your opponent kills you, and your opponent doesn't have a counterspell or some other cheap, efficient answer. For specific examples, see AwesomeButImpractical.Magic The Gathering.
Awesome yet Practical: The game designers like powerful, tournament-dominating cards to be exciting and fun to play, so it's common to see exciting and fun cards intentionally pushed up in power level. Planeswalkers are a great example: their characters are designed to be the face of the game, so the developers make sure to give them powerful abilities. Jace, the Mind Sculptor in particular quickly gained a dominating presence in multiple tournament formats, so much that Wizards was forced to ban him from certain formats.
Blessed with Suck: Many of the extremely mighty creatures (Darksteel Colossus, Serra Avatar, ...) have an ability that puts them back into the deck every time they hit the graveyard. Sounds great, until you realize that this is a deliberate safety measure to prevent players from discarding and reanimating them, thus circumventing paying their steep cost.
While it's entirely possible to build decks on a budget, Magic is expensive for the serious player or collector. Prices for tournament-winning, in-print single cards have routinely exceeded $20, and sometimes even approached/exceeded $100. On top of that, the most popular and common tournament formats rotate new sets in and old sets out each year, serving the dual function of keeping the game fresh and keeping Wizards in business selling new cards.
Duels of the Planeswalkers and its sequels. While you can unlock any and all of the cards in the game through gameplay, you can also buy DLC that unlocks the thematic decks of the planeswalkers featured in the game. Doing this unlocks all the cards in that deck, meaning you can now use them to customize yours.
Card Battle Game: Most video game adaptations, including the Microprose Shandalar game and Duels of the Planeswalkers.
Aside from the infamous Channel-Fireball combo, planeswalkers fall under this as well: Some of their ability require the removal of loyalty counters. These same counters effectively act as their life totals; once they're out of counters, they're gone. Most also invert this trope by having abilities that give them loyalty counters as well, as well as a few with abilities that do nothing to their counter totals.
Phyrexian mana symbols from New Phyrexia: For each Phyrexian mana symbol in a cost, you can pay 1 mana of the specified color, or 2 life.
That card is an embarrassment to card design. I actually had zero to do with the card and I'm still embarrassed. We took two iconic beloved cool legends and combined them into a pile of, well a word I'm not allowed to use on this site. Of all the balls dropped with the design of legendary characters, this is one near the top of the list. My humblest apologies.
The boss characters in the Duels of the Planeswalkers games often have decks that are considerably stronger than the default characters' decks (most of them can't be unlocked either). Karn in particular uses several cards that are outright banned in nearly every format in the physical card game and is capable of killing you on turn 3 in a game where most games tend to go more than 10 turns. If you manage to win against him, it's likely because you got lucky.
The encounters in Duels of the Planeswalkers 2013 take it even further. Given that the opponents in these games follow a certain pattern, you can expect them to have more than four copies of a card in their deck.
Conservation of Ninjutsu: In a weird way, the Exalted effect can become this. Cards with exalted give +1/+1 to attacking creature the player controls, but only when it's attacking by itself. Many cards with this ability are mere 1/1s - not very scary by themselves, but get a handful and you can attack with a nice big 10/10 in no time.
Counterspell: Loads and loads of examples, including the Trope Namer. Each card in a player's deck is considered a spell, and cards with the types "Interrupt" or "Instant" may be played in response to other spells — such as those your opponent tries to play. The modern standard for counterspells in Magic is Cancel — as in, "I cancel your spell."
Damage Over Time: Several cards deal damage during a player's "Upkeep" step, in contrast to most cards which can only deal damage once at a time.
Dangerous Forbidden Technique: Applies to a few combo decks, especially combos that are Cast from Hit Points. (Channel-Fireball is a good old-school example: you pay all of your life, but the resulting fireball kills your opponent in one shot.) What makes them so dangerous is the likelihood that if they fail to kill the opponent dead then and there, the Cherriest of Taps will be your doom.
Or rather, "being removed from the game is cheap". Most permanents and spells that are destroyed, discarded or otherwise gotten rid of go to the graveyard zone by default, but ever since the game was new a few abilities here and there send their targets or themselves to the "removed from game" zone. But such effects have slowly become more common over the years, and two cards were printed that retrieved any card that had been removed from the game, and variations on the effect like suspend have proved very powerful and popular. So in a 2009 rules change, the description of the "remove from game" effect was changed to "exile", to reflect the fact that there's a good chance it hasn't been "removed from the game" at all.
Mocked by the unhinged card "AWOL", which first removes an attacking creature from the game, and then takes that creature from the "removed from the game" zone and puts it in a state called "absolutely-removed-from-the-freaking-game-forever".
Defeat Means Playable: In each edition of Duels Of The Planeswalkers, you unlock each deck by defeating an AI opponent using it in campaign mode, except two starting decks.
Depending on the Writer: Or rather, Depending On The Design Team. For entire sets. The company is always struggling to deal with Gameplay and Story Segregation, and exactly how the game is supposed to represent an actual wizards' duel. At the moment they seem to have settled on a balance the company likes, but it still changes a little with every new set, partly as they iron out tiny details and partly as another potential way to add variety to the game. A few examples of the ways this goes back and forth:
Early in the game, many big blue creatures (like Sea Serpents) could attack players that didn't control any islands only with difficulty, if at all, to symbolize that they were natural aquatic monsters and therefore couldn't leave the water. That effect still appears occasionally, but is much rarer now, partly because designers have decided it's less fun to have creatures with such severe restrictions on attacking and partly because the idea that lands actually represent physical terrain on which creatures are fighting raises more questions than it answers. (For a time, Merfolk were taken out of the game for this flavor reason, until they decided to use the Fredericka Bimm Method of merfolk shapeshifting.)
Creature types have come and gone and been standardized several times. At the moment, humans are the Jack of All Stats: represented more or less equally in all colors but with no Human-specific racial bonuses. Most colors have one characteristic racenote Merfolk for blue, zombies and vampires for black, goblins for red and elves for green full of small, cheap, quick and/or utility creatures, each color has one iconic racenote Angels for white, sphinxes for blue, demons for black, dragons for red and hydras for green, and a few other creature types are much more common in one or two colors than the rest. The thing is, this leaves many creature types from fantasy stories or previous Magic sets unused just because that design space is already taken. Orcs, for example, appeared in early sets, but they eventually fell into the niche of "like goblins, just a little taller" and stopped being used soon after that. Merfolk didn't appear for a long time for the same reason that sea monsters' inherent weakness was dropped, but as soon as designers figured out that they could be bipedal - sort of like Fish People but not as ugly - they were brought back.
Disc One Nuke: Throughout the game's history, cards like Tolarian Academy, Sol Ring, and Black Lotus that allow you to play other, more powerful spells in the early turns have been consistently dominant, comprising a large portion of the game's banned cards.
Equivalent Exchange: A key part of the game, every spell you cast or ability you activate has some sort of exchange going on. Even the most simple of cards require you to generate mana and fill precious deck slots with the given cards to work. Some more elaborate spells ask for more tangible costs such as life payments, discarding cards, or sacrificing permanents. Most of the game's problems have come from cards doing far more in return for what you paid for them...
Expansion Pack: Each set is an expansion to the ever-widening game, though each block can be played independently as well. Within a block, each subsequent set is an expansion to the first.
Fan Nickname: Lampshaded. Morphling earned the nickname "Superman" for its high power level at the time. So when the designers made an enchantment that could give Morhpling's abilities to any of your creatures, they called it Pemmin's Aura—an anagram for "I am Superman."
Fan Speak: Magic players have created an extensive vocabulary of slang terms and technical jargon. This Useful Notes pages has some examples.
Fastball Special: Stone Giant, among others, can be tapped to hurl a creature into the air to attack your opponent directly or block an enemy flyer. This is generally not a survivable experience for the creature.
"Freaky Friday" Flip: Some spells and abilities can inflict this effect, exchanging players' cards-in-hand, permanents-in-play, or even life totals, the last one being a popular trick in combo decks.
Gambit Pileup: Due to the nature of the stack, players can find themselves fighting a mini battle in which they're undoing each other's move, for example:
Player 1: Shock on Player 2's Merfolk Looter. Player 2:Unsummon on Player 2's Merfolk Looter. Player 1:Counterspell on Player 2's Unsummon. Player 2: Counterspell on Player 1's Shock. Player 1: Counterspell on Player 2's Counterspell.
And so on. If they do this by piling the cards onto each other (or playing online), then the trope is being played literally.
Early sets tried to avert this to a degree with mechanics such as islandhome, which stopped sea-based creatures from attacking opponents who don't control an island, and causing them to cease to exist if their controller controls no islands. This was a rather clumsy and unpopular solution, and R's current policy is to ignore moments of Fridge Logic in favour of gameplay. (After all, you are a wizard!)
Another common example are Equipments, a subtype of Artifacts that can be, well, equipped to your creatures. Often it works well, almost as often it results in humongous axes being wielded by a little bird, or magical armor being worn by a tree. Indeed, under certain circumstances you can end up putting cranial plating on a mountain.
Many combo decks, as well as many linearly-focused decks like the Affinity deck of the Mirrodin era, are incredibly powerful if the opponent has no way to interact with them, but vulnerable to being completely shut down by a single "hoser" card that can disrupt them in the proper way.
Lots of creatures have large power, but only one toughness. There's also a literal Glass Golem.
Golden Snitch: Alternate win condition cards can be sprung without warning. Even decking can be considered this, if the winner was at 1 life and the loser was at a whole lot more. Many of these alternate wins are hilariously impractical and for all the time and resources you spend setting one up it's usually just easier to win the old-fashioned way, but Rule of Cool means people love these things anyway and will often bend over backwards to pull one off. A partial list of individual cards that create alternate win conditions can be seen below under Instant-Win Condition:
Or, as development team member Tom LaPille puts it:
Our vision of New Phyrexia—as created by Aaron Forsythe and Ken Nagle, the two players in R&D with the strongest griefing tendencies—is one of all-upside griefing that leaves your opponent not knowing what they're supposed to do and feeling a little bit violated. Phyrexia doesn't destroy all the creatures on the battlefield; it destroys all the creatures on the battlefield and rips some out of your library to boot. Phyrexia doesn't just exile a permanent. It disallows the opponent from casting every other copy.
History Repeats: Literal example in the Time Spiral block, which brought back lots of old cards and themes as part of its "time" gimmick.
Hit Points: 20 for each player to start, though it can get very low, very high, and some cards even let the player keep goingwith 0 or less. Creatures also have these (in the form of toughness), but theirs reset each turn as long as they take less-than-fatal damage. Planeswalkers have Loyalty points which work a lot like the player's hit points.
The sliver race. Slivers don't just have Haste, their abilities generally read like "All Slivers have Haste"; there is at least one sliver for every ability with a name and even some slivers with no ability, they just exploit others'. Naturally there was also the SliverQueen, to which succeeded the Sliver Overlord, to which succeeded the Hive Mind itself, with its newfound consciousness.
The Selesnya Conclave apparently also has a weak Hive Mind of some sorts. Hinted at by the Convoke mechanic.
The Hive Mind card causes players to share spells.
Instant Awesome, Just Add Dragons: One of the unwritten rules of Magic expansions is that there must be dragons in every set. Even in Ravnica, where dragons are extinct, there's dragons anyway. Why? Because dragons are awesome.
Instant Awesome, Just Add Ninja: Pretty much as soon it was decided that the Kamigawa block would be based on medieval Japan, ninjas inevitably snuck in (and went on to be one of the most popular aspects of the set in which they appeared). The longer version of the story is here.
Intentionally Awkward Title: The name of the game itself. You can either call it "Magic" (and risk confusion) or "Magic: The Gathering" (which is harder to say). The reason it's called "The Gathering" is for trademark reasons; the word Magic is too generic to be trademarked, and magic card tricks are pretty common, so the name was to apply to the Alpha/Beta/Unlimited sets. Richard had planned sequels named "Magic: Ice Age" (which was eventually released as Ice Age block) and "Magic: Menagerie" (which was released as Mirage block). However, the game was so popular that the company demanded an expansion pack much earlier than expected, resulting in Arabian Nights and, eventually, the "sets" we know and love today; the requirement that every card have identical back sides means that we're still stuck with "Magic: The Gathering" as the full name. (Not to mention a million angry fans would descend upon Wizards' offices in hordes if they ever changed it.)
Joke Character: Variation: each block typically contains at least one entirely awful card, deliberately put there just for the people who love to try and make it work. The game is such that they usually can.
A Kind of One: It was common in the game's early days for creatures to have unique creature types based on their names, leading to types like "Aladdin" or "Uncle Istvan". Most of them are now defunct, but a couple of these odd one-of types had the honor of later being upgraded into their own races: notably, Atog and Lhurgoyf. Some just stayed as one-ofs, like the solitary Brushwagg.
Kingmaker Scenario: Frequently crops up in multiplayer games when Bob's position is too weak to win the game, but strong enough to pick a side and swing the game in favor of either Alice or Carl at his whim. And, of course, Bob can improve his position quickly when down to a duel, culminating in a Dark Horse Victory if he chooses wisely.
The Magic 2010 reprint of Lightning Bolt (A very popular card that hadn't seen print for a decade) has flavor text about a wizard who is surprised to have called upon such power as he hadn't seen since his youth.
Jace, the Mind Sculptor's ultimate ability wipes the target's mind clean by deleting their entire library and temporarily blocking access to their hand.
Cards like Surgical Extraction and Memoricide. The latter allows you to name a card and exile all of your opponent's copies of that card—out of their hand, graveyard, and library. The former allows you to do the same with a card already in that player's graveyard.
Amnesia discards all the spells in your opponent's hand.
Lion's Eye Diamond was originally designed to be a Black Lotus tweak so bad that no one would ever play with it. It's now banned or restricted in almost every format.
Grindstone started as an oddball Millstone variant that saw little to no serious play. Many years later, Wizards printed Painter's Servant, and a turn-one Vintage or turn-two Legacy combo-kill was born.
Dark Depths saw little play when it was originally released. In the Zendikar expansion, Vampire Hexmage was printed and within weeks, Vintage and Legacy players discovered the combo that netted a player an inexpensive, indestructible, flying 20/20 creature that could win the game for them the following turn.
Tarmogoyf was printed in Future Sight so that it's reminder text could hint at the upcoming introduction of two new card types (Planeswalker and Tribal). However, it turned out to be so effective that it's now the most expensive card printed in the last ten years.
Cards from the silly, silver-bordered sets Unglued and Unhinged aren't tournament-legal, but can be surprisingly effective at the kitchen table.
The Japanese version of Yawgmoth's Agenda was mistakenly translated as Yawgmoth's Day Planner.
The Spanish version of M10's Jackal Familiar mistranslated "Jackal Familiar can't attack or block alone" as "Jackal Familiar can't attack or block." That would make the card significantly worse, wouldn't it?
The Spanish version of the M11 card Disentomb mistranslated "Return target creature card from your graveyard to your hand" as "Return target creature card from your graveyard to play". That would make the card significantly better.
The Portuguese version of Stoic Rebuttal does... well, nothing. Stoic Rebuttal is a simple counterspell that costs 1 less mana to cast if you have 3 or more Artifacts. Too bad when they translated it, they forgot the whole "counter a spell" part. Ooops.
Luckily, cards use their English oracle text, no matter what is printed on the actual card.
Some of the more creative strategies border or flat out are this. Most infamously, and maybe apocryphally, the player who multiplied the effect of Chaos Orb by ripping it into pieces and scattering it over his opponents side.
Or the player who brought to a tournament a deck based around Wall of Roots, whose ability you can activate only once per turn... and convinced the judges that he could use it infinite times by activating it between turns.
Magikarp Power: Flip cards from Kamigawa block and Level Up creatures from Rise of the Eldrazi tend to start out worthless and eventually become very powerful. The double-faced Transform cards from Innistrad block have a similar vein.
Master Of All: The closest to the spirit of the trope is probably Progenitus, which at 10/10 is among the largest naturally-occuring creatures and has Protection from Everything. (Protection effects are usually limited to a single color or creature type.) Fittingly, it costs two of every mana type to play, requiring the player to be something of a Master Of All just to get it on the field.
Maximum HP Reduction: Creatures with the Wither or Infect abilities deal damage to other creatures in the from of -1/-1 counters. Unlike regular damage, which creatures heal from at the end of each turn, -1/-1 counters represent a permanent reduction in both power and toughness (having toughness reduced to 0 will kill a creature) for as long as the creature is in play.
Multiple Demographic Appeal: The minds behind Magic R&D have actually created three psychographic profiles — "Johnny", "Timmy", and "Spike" — representing three different demographics for the game. See Timmy, Johnny and Spike Revisited. Simply put: Timmies love to play cool cards, Johnnies love to design cool decks, and Spikes love to win. Since then, the flavor gurus created two more profiles — "Vorthos", who likes the flavor aspect of a card, and "Melvin", who likes the mechanical aspect of a card.
If you are playing in a multiplayer game and you die, all the cards you own disappear from the game. This is primarily so that you don't have to stick around until the end of the game just to get back the enchantment you put on somebody else's creature.
Many white removal spells (such as Oblivion Ring and Journey to Nowhere) work like this on a smaller scale, only functioning for as long as the removal card itself stays in play.
Abilities themselves avert this; they exist independent of their source, so that destroying the source does nothing to stop the ability.
Eldrazi. Again. Is there any trope they don't fall under?
Not the Intended Use: Rampant. Destroying your own creatures, countering your own spells, using a War Barge on your opponents' creatures and then destroying the barge to kill the creatures, ripping up your Chaos Orb before you activate it... On rare occasions a player will use a harmful spell on themselves or helpful spell on their opponent because the game has reached a weird point so they actually want to do what would normally be bad. Very often, though, players will cast spells just for side effects that are normally minor, but happen to be incredibly important at the time.
Not Using The D Word: References to demons were removed after a few Moral Guardians complained; this carried on for a while with cards being called "horror" or "beast," before demons started appearing again. This is why the Unglued card "Infernal Spawn of Evil" has the text "Summon Demon Beast" and vice versa for the Unhinged card "Infernal Spawn of Infernal Spawn of Evil."
The Portal expansion was followed by Portal Second Age and Portal: Three Kingdoms.
Head Designer Mark Rosewater has a little fun with it here, with a fake announcement for Homelands 2: Grandmother's Return. He also laments that his suggestion for Portal 2: Electric Boogaloo was rejected.
The cancelled sequel to Unglued was tentatively named Unglued 2: the Obligatory Sequel.
Old Save Bonus: Duels of the Planeswalkers 2013 gives you a free deck key (which immediately unlocks all locked cards or turns non-common cards into foil versions for one deck) if you've played Duels of the Planeswalkers 2012.
Painting the Medium: The players are Planeswalkers, immensely powerful wizards who summon monsters and cast spells in battle with other wizards. There are actual planeswalker cards, which are treated like another player, with their own life count and unique "spells".
Played for Laughs: Some cards, while still useful, have the ability to cause some much needed hilarity amid all of the chaos and destruction. For example, Turn To Frog.
Experiment Kraj copies all the abilities of creatures that have +1/+1 counters on them.
Power Creep: Of a sort. Creatures started rather poorly and rose in power and usefulness over time (compare Alpha's Force of Nature to Zendikar's Terra Stomper, both 8/8 green creatures with trample, but the later one is much better), while some early spells were considered too powerful and weaker versions were released to replace them (Counterspell vs. Cancel). Cards that experience either are often considered "strictly better/worse".
Powers as Programs: Creature enchantments are this. As are equipment; yes, it's possible for a bird to carry three swords, a shield, and armor clearly designed with humans in mind. Could they be Morph Weapons? It sounds like something a Planeswalker could do, but we might never know.
Power Equals Rarity: An interesting case. Although many rares are more powerful than their common or uncommon counterparts, powerful cards are not exclusively rare. Additionally, rarity is used to balance Limited formats (in which players build decks out of a random or semi-random pool of cards). And this is only scratching the surface—whole essays can (and have) been written on the guidelines the designers use to determine rarity.
Power of the God Hand: Not In-Universe, but used as fanspeak. A different definition of "hand" than most uses of this trope, but a "God Hand" is generally considered seven cards that, when drawn, will defeat an opponent in the first round. The exact definition of a God Hand can sometimes be a source of great contention.
Magic: The Gathering Online's "Vanguard" has several Vanguard avatars which pull random effects like these. Most prominently, Momir Vig allows you to pay X mana to make a copy of a random creature that also costs X mana, spawning an entire alternative format called Momir Basic, where players build a deck using only mana sources and a Momir Vig avatar and battle with randomized creatures from all over Magic. Jhoira of the Ghitu has a similar effect for instants and sorceries; likewise with Stonehewer Giant and equipment.
Strategy, Schmategy has you roll a six-sided die to determine which of five totally unrelated abilities you'll get when you cast it. To up the ante, one of the options is "Roll the die two more times."
The original Microprose video game tried to take advantage of the format, with several cards that were created that had effects that were random.
Rated M for Manly: They tried to do this by kicking Rebecca Guay, one of the artists who draws the portraits for the cards, because her art was "too girly". After widespread criticism from fans, they reinstated her. This was lampshaded in the Unhinged joke set with the cards "Persecute Artist" and "Little Girl".
Weenie decks can be this sometimes, as your weak creatures take heavy losses but continue trying to swamp the opponent anyway. This is particularly true in the case of tokens; cheap, disposable creatures usually generate en masse from other cards. As an inversion, a particularly successful weenie or token attack with few casualties becomes a Zerg Rush instead.
A interesting example is the Eldrazi who use mobs of Eldrazi Spawn Tokens to provide the mana needed for summoning bigger creatures.
Retcon: The rules of Magic have undergone many changes, the largest having been the complete overhaul of the game's timing system with the release of Classic Sixth Edition. Cards are frequently given new official wordings ("errata") so that they continue to work properly after each change of rules.
The original sphinx, Petra Sphinx, had players guess the top card of their libraries. This same guessing game was also used for Conundrum Sphinx.
Sphinx of Uthuun gives your opponent choice of which cards to put into your hand.
Isperia the Inscrutable rewards you if you can correctly guess a card in your opponent's hand. Of course, since they have to reveal their hand if you guess wrong, the riddle is a lot easier the second time.
Sphinx Ambassador secretly chooses one of your opponent's creatures, and if they can't guess which one, you get to steal it.
Even sphinxes who don't have riddle-related gameplay will often reference riddles in their Flavor Text, because hey, that's what sphinxes do.
Both Johnnies and Timmies will play cards just because they do something cool, though for different reasons.
Also sometimes used to justify breaking the rules of card design. Form of the Dragon does a lot of things that, in terms of game mechanics, red spells don't normally do. It's okay, though, because the card TURNS YOU INTO A DRAGON!
Cards like Skullscorch, Dash Hopes, and Lava Blister give your opponents the ability to jump in front of them to stop the spell's effect, taking heavy damage instead.
Perplex: if you want to keep your spell, you'll have to discard your hand...
Effects that cause your opponents to sacrifice a creature (Or any permanent, really). One of them must die...make your choice.
Played with in the card It That Betrays, which possesses an ability that forces your opponent to sacrifice two permanents whenever it attacks. While this is true of all Eldrazi, It That Betrays resurrects said permanents under your control. Now not only do they choose who they have to let go of, but also watch as it's reborn into your service.
A number of schemes in Archenemy allow the villain to offer an opponent a choice between "you take a big effect" and "each of your allies takes a smaller effect."
There are a few blue cards, such as Fact or Fiction and Gifts Ungiven, that invert this to an extent—instead of forcing your opponent to choose what they want to lose, it forces them to choose which of a selection of cards they want you to gain.
Even before New Phyrexia, the Mirrans had Painful Quandary, which, every time an opponent casts a spell, requires he either discard a card or lose five life. Remember, that's a quarter of your starting life.
Serious Business: Tournament Play. This makes sense, because Wizards of the Coast provides some serious prize support. A single tournament can net the winner upwards of $40,000, and they've given away over $25 million in total cash prizes since they started running major tournaments. Several players have lifetime winnings in excess of $100,000, and that doesn't count minor tournaments or free plane trips to exotic foreign locales (though admittedly, you're there to play Magic, so perhaps "dreary foreign convention center floors" would be more accurate). Of course, this trope often appears in full force even when there isn't a pile of cash at stake.
Unglued also contained the card(s) with the largest mana cost, the aforementioned B.F.M., whose 15 black mana symbols stretched across the entire top line of the card. Once again, Unhinged decided to top it with Gleemax, a card which costs 1,000,000 mana. Yes, that's one million mana. I hope you brought your Mox Lotus.
The Urzatron, a set of three lands (Urza's Mine, Urza's Tower, Urza's Power Plant) first printed in Antiquities. If you control one or two of the set, they each produce one colorless. Control all three, and two of them produce two colorless and the Tower produces three.
Tech Tree: The Level up mechanic from Rise of the Eldrazi functions as a Tech Tree, allowing you to invest additional resources into one of your creatures to upgrade it with new abilities.
Teleportation Sickness: Summoning sickness, which prevents creatures from tapping and attacking on the turn they're summoned. The story justifies it as a form of great nausea. Averted by creatures with Haste.
"Banding" and "Bands With Other" were so complex that they are among only a stark few keywords that they simply stopped printing entirely.
"Phasing" as well, due to the unusual and unintuitive ways that it works (permanents phase in or out on each of their controller's untap steps, and the rules have changed multiple times as to whether this triggers "enters/leaves the battlefield" effects or not. Currently not.)
There's also the rules about continuous effects and layers, which are relevant in every format and even more complicated.
Too Awesome to Use: The very first edition included the ante system, which allowed the winner of the match to take some of the loser's cards. This made players very reluctant to add very rare, powerful cards to a deck.
The Unreveal: Mark Rosewater loves to do this. For example, he once replaced most of the words in a spoiler laden paragraph with the word "goblin".
Goblin of the Goblins is going to be a goblin built around the Goblin goblins, all of which have no goblin and are goblin. For example, there are two Goblins at goblin, the goblin of which is 7/7. All of the Goblins have a new goblin called goblin. Goblins with goblin have a goblin; whenever a goblin with goblin goblins, the goblin goblin must goblin that many goblins. The Goblins are very goblin but there are goblins that can create 0/1 goblins called Goblin Goblin that can be goblin to goblin one goblin goblin to your goblin goblin and will help you be able to goblin the Goblins. In addition, the goblin has a new goblin called goblin goblin. You may spend goblin on goblin with goblin goblin to improve their goblins and goblins. This Limited goblin is much goblin than the one in Goblin.
This is what it actually says
Rise of the Eldrazi is going to be a set built around the Eldrazi creatures, all of which have no color and are giant. For example, there are two Eldrazi at common, the smaller of which is 7/7. All of the Eldrazi have a new keyword called annihilator. Creatures with annihilator have a number; whenever a creature with annihilator attacks, the defending player must sacrifice that many permanents. The Eldrazi are very expensive but there are cards that can create 0/1 tokens called Eldrazi Spawn that can be sacrificed to add one colorless mana to your mana pool and will help you be able to cast the Eldrazi. In addition, the set has a new ability called level up. You may spend mana on creatures with level up to improve their stats and abilities. This Limited environment is much slower than the one in Zendikar.
Shelkin Brownie's special ability is to remove the "Bands with other" ability from creatures. In the history of Magic, there are two cards with the "Bands from other" ability: the 1/1 tokens created by Master of the Hunt, and the Unhinged card Old Fogey, which is illegal in every format and only has the ability as a joke (the only creatures he can band with, aside from creatures that have the regular Banding ability, are other copies of himself). Oh, plus a cycle of lands that are serious contenders for "Worst card in the game" and probably shouldn't count. Good old Shelkin Brownie, keeping the world safe from four-mana 1/1s and legendary lands that don't produce mana!
The infamously bad card Great Wall is an enchantment that stops creatures with the Plainswalk ability. At the time of its printing, this included exactly two cards, both of them craptastic: Righteous Avengers, a 3/1 for 5 mana with no other abilities; and Giant Slug, which could only gain Plainswalk by paying 5 mana a turn. Good thing we built that wall, right?
Standstill: They play spells, you draw a whooping three cards. They don't play spells, you get an advantage provided you built your deck around this being beneficial.
Choice of Damnations: Your opponent chooses a number, and you then decide whether he loses that many life points or keeps that many permanents, while the rest is sacrificed. (A low number would mean that your opponent loses almost all of his cards, and a high number would mean a large life loss.)
Mass creature removal, such as Wrath of God: Control decks use these mostly against aggro, so aggro players will find themselves having to restrain their use of creatures, lest they all be wiped by a single card, but then he may be heading for a late game, in which control decks have advantage over aggro decks.
Various creatures have effects if they're blocked, punishing the blocking player. Of note is Slith Strider, which has an ability that triggers when it's blocked, and one that triggers when it deals combat damage to a player.
Ichorclaw Myr: Take the attack and gain a poison counter (possibly more if it gets buffed), sacrifice a low-toughness creature to absorb the attack, or have a big beastie suffer a sizable, permanent power/toughness loss.
Phyrexian Obliterator cruelly employs this trope. While its earlier counterpart, Phyrexian Negator, actually encouraged the opponent to deal damage to it so that the controller would have to sacrifice something, Obliterator turns that around and makes it so that whoever's responsible for the damage has to sacrifice permanents. It can be a pain for your opponent to get rid of without causing its ability to go off. Oh—it's also an undercosted trampler, so they'll have to block it and/or destroy it, or it'll destroy them in 4 turns flat.
Vexing Devil gives the enemy player a choice of either being punched in the face by a uber-lightning bolt, or having to face down a 4/3 on turn 2. For the record, a creature was considered tournament-worthy if it could get down as a 3/2 on turn 2.
"YEAH!" Shot: Used in a photo◊ from the official coverage of Day 3 of the Pro Tour: Dark Ascension tournament; it's a group shot of the Top 8 all in mid-jump.
Your Mind Makes It Real: The entire point of the Illusion tribe of creatures. They can kill other creatures and deal damage to players and planeswalkers just like any other creature, but if they are targeted by anything, they die.
As mentioned above, aggro decks, especially "weenie" decks. Most (in)famous are Goblins (the Little Red Men), White Weenie (soldiers, knights, and birds of prey), and the Mirrodin block's Ravager Affinity (a rapid-fire Game-Breaker-laden deck which can inflict sudden death very rapidly on a good opening hand).
Kuldotha Red. Capable of (potentially) producing as many as seven creatures in turn one.