In this game, it's not just a moment that lets you enjoy the flavor. It can also lead to some powerful combos.
In Return To Ravnica, the Azorius were given an entire runic alphabet, as seen in many of their cards. It's quite an interesting embellishment, until you realise that "rune" comes from the Indo-European root "reu", which is also the root for Ouranos and Varuna. Both are sky deities; which colour pair focuses on flying and the sky again?
Do you know why the Innistrad pack was delayed into 2011/2012? Think about it; wouldn't a world where all hope is being lost fit well into an year were everyone is paranoid about the end of the world? And now with Avacyn Restored, the up-beat ending after so many downer endings sounds like reassuring that good will triumph in the end.
Even better, add up the number of cards in the Innistrad block and you get a grand total of 666. Makes perfect sense that there are 666 cards to collect in a set based around demons, vampires, werewolves, zombies, and Sealed Evil in a Can.
Many cards contain subtle shout-outs to other cards that fall under this trope. For example, it's easy to notice that Fortune Thief is a throwback to the Arabian Nights card Ali from Cairo, but if you look closely at the art, you can see that the Fortune Thief has the same ability because she stole Ali's magical amulet. There are numerous other examples, most of which are pointed out on the official website's "Magic Arcana" feature here.
In the Scars of Mirrodin set for Magic: The Gathering, the Phyrexians logo is a circle with a line through it. To put it in other words, its the lower case greek letter Phi. As in Phi-rexians. I facepalmed when I realized the connection.
Also note that phi is the symbol for the golden ratio... an antiquity mathematical value often attributed to perfection.
Speaking of which, I initially thought the "pay 1 life" thing was bad, but then I realized Yawgmoth's Bargain turns a plain ordinary Healing Salve into an Ancestral Recall. Awesome.
Also note that the new White Phyrexians have as their defining feature the fact that their skin was flayed and replaced by white, porcelain covering. The end result is that many of them look somewhat skeletical, specially when combined with their exposed muscle tissue. This is likely a call back to Kamigawa, in which several villains were White since that is the colour of death in traditional japanese culture, and indeed some Red and Black spirits of the same setting were also naturally coloured that way (specially Yuki-Onna and Kemuri-Onna).
My basic thought upon seeing the various "seals" of Ravnica (which were basically instants like Terror and Shock redone as enchantments that would have the effect when sacrificed) was "hmm, vaguely interesting, but it does mean the opponent knows what's coming". Then I remembered one of the guilds of Ravnica thrives on having no cards in your hand, meaning that having a spell sitting out in the open in enchantment form waiting to be used is actually a tactical advantage. - Count Dorku
Oddly, they didn't print the entire Seal cycle - only the black Seal of Doom, and the red Seal of Fire. Hmmm, what colours was the guild that cared about having an empty hand again?
Necrogen Scudder was the only Phyrexian card in Scars of Mirrodin that didn't feature infect, proliferate, -1/-1 counters, or other Phyrexian mechanics and was not legendary like Geth. But it does require you pay 3 life. The Mirrans got all the lifegain, and a card which prevents life loss altogether, while Phyrexians got most of the life payment. But then you realize that Phyrexians don't care about life (since they win by poison counters) and are happy to pay it, as shown by Phyrexian mana cards.
The Phyrexian factions were shown out of place in the Planeswalker's Guide; instead of the usual WUBRG, it was WBUGR. While it was arguably to make the Red phyrexians' goodness an epic reveal, it can also be indicative of which colours are more naturally phyrexian, starting with the highly dogmatic and organised White and ending with the freedom loving Red.
Bronze Bombshell seems to be a fairly obvious pun on "blonde bombshell" that happens to actually be a bombshell. But why is it an artifact creature? It's an objectified woman. Chimaera
No, it's even better: it's a blow-up doll! — Troacctid
The Helvault is like Pandora's Box. It contains all the evil in the world. Once opened, all the evil comes out along with hope. Which in this case means Avacyn. PMiller1
The Dark Ascension set brought in the red/green "Immerwolf," a Wolf creature which gives a boost to all Wolves and Werewolves, and, while it is in play, non-Human Werewolves cannot transform. So any Werewolf that has transformed into its stronger monster state stays that way. Why is this brilliant? It's all in the name. "Immer" is the German word for "always." So "Immerwolf" means "Always Wolf," as in, "Your Werewolves will stay Wolves."
The Dimir-colored 20-sided die is blue and black, which are very difficult to read from across the table unless the light is just right. How fitting for the guild of secrets and sneaking...
With the ascension of Xenagos to the Therosian pantheon, they number 15: 5 mono-color major gods, and 10 multicolor minor gods. But there wasn't an RG god before Xenagos ascended. Why not? Look at what Xenagos does immediately upon apotheosis: he takes an ordinary "Hey we won a war!" festival, cranks it up to 11, and sends it rollicking across the plane like a cross between a hurricane and a bacchanalian orgy. This has probably happened before, possibly with an ancient god of revels born of Nyx, and he was killed too.
Eldrazi Spawn tokens. Eldrazi Spawn. As in, children. You sacrifice them to add mana, most likely to summon the big Eldrazi.
The Eldrazi get even scarier when you examine them. Not only are they meant to be reminiscent of Cthulu, but they become even more terrifying when you realize that while they're colorless, they're also not artifacts. They have somehow managed to transcend "mere" things like the five colors that so much of the Magic Multiverse revolves around. Not even Nicol Bolas, the most powerful "old" planeswalker left alive, managed that trick.
Since the Eldrazi essentially devour every Plane they come across, another, less Fridge Horrific explanation is that they're either from a Plane with completely different rules (and that nobody can go to because it's already been eaten), or from somewhere outside the Multiverse entirely.
It has been stated that the Eldrazi come from the Aether, not any given plane that may or may not have existed. The Aether is the channels between planes, as in, the thing Planeswalkers use to travel between planes. They didn't have any affiliation (not even colourless...They were something transcendent of everything) but gained their colourless status when they were imprisoned on Zendikar, as the only way for the Planeswalkers of old to achieve this was to have Sorin pump them full of colourless magic, and the other two trap them. - Brownie.
Actually Sorin lead them to Zendikar, where Ugin would blunt their attacks with his "ghostfire" and used his knowledge of colorless magic to bind them to the world. The lithomancer created the prison.
The Dredge keyword. At first, it seems simple enough - you mill yourself to get something lost. Then, you remember that, in Magic, your Deck means your memory. Basically, in-flavor, to use Dredge, you need to sacrifice your sanity
Actually, in Magic, your deck is called a 'library', which is basically your spellbook. Therefore, it's more like erasing stuff from your spellbook that you can re-write later.
Whilst it's called a library, fluffwise it's your memory (library = all the spells you know, hand = the handful (geddit?) of spells you're thinking about at any given moment). Library is just a fantasy word that vaguely has to do with what the deck is. It could also do with the evolution of the game's fluff: in the early days the deck might have represented your spellbook, but it means memory at this point.
Also consider cards like Jace, Memory Adept; Jace, the Mind-Sculptor; Traumatize; Mindcrank... This list could go on forever. Quite a lot of the cards that have to do with milling are about memory, mind, and/or sanity.
Oddly, it's pointed out to you, but you just don't think about it. Mostly it's "Sacrifice a creature:...", which seems like it's as in "sometimes we need to make sacrifices", before you remember the players represent wizards and sorcerers. Eldrazi Spawn tokens take this to a whole new level: You can sacrifice them to generate one colorless mana each, which you'll most likely use to summon the huge, Timmy-favored, Troperrific (Master Race, Eldritch Abomination, Non-Elemental, etc. etc.) Eldrazi. Yes, the Eldrazi eat their children.
A friend came up with an idea that makes it a bit less horrific: The spawn are simply mana made flesh, they have no real conscience. The reason they can be sacrificed is it lets the mana flow into the world. The Eldrazi eat mana. You don't so much summon Emrakul, as the spawn go to wake him up. Like an alarm clock. When there's 15 of them poking his head, he rolls over to get up and squashes them, devouring the mana they once held.
Not so bad if you understand the premise of the game. The players represent planeswalkers, powerful wizards who have developed the ability to shift from one plane of reality to another, each plane manifesting as some sort of world. The battle between players is to decide who controls the plane that they are on at the time, and all of the cards represent the memories of the planeswalkers. The lands represent all the places they've been to, and recalling them allows the planeswalkers to call forth the mana that flowed through that land. All of the creatures are sort of Platonic forms: Idealised representations of some remembered creature, made manifest by the planeswalker converting the mana into a physical form with a purpose. Sacrificing a creature merely means dissolving the integrity of the magical construct in such a way that the energy can be directed to some other purpose.
With the introduction of the word "dies" into the official jargon, it could literally mean you're not summoning an idealisation of the creature, but the creature itself, which can then die a horrible, horrible death.
Magical copies can "die" or cease to exist as well. The term was mostly introduced because everyone was using it to describe a creature hitting the graveyard, and it's a lot shorter than "creature goes to the graveyard from play."
By contrast, because goblins are Too Dumb to Live, sacrificing a goblin is funny. Or Mogg Fanatic (sacrifice to do 1 damage to anything), bloodfire cards (sacrifice to do damage equal to its power to everything), and Goblin Grenade (sacrifice a goblin to do 5 damage to anything).
Token creatures in general fit this trope, as they were mostly created by some sort of (usually asexual) reproduction. They were born to fight.
Certain tokens, such as Tuktuk the Returned and the Marit Lage tokens are meant to represent the great deity the base cards summon, after a certain condition are met.
Titania's Song (makes artifacts into creatures with power and toughness equal to their mana cost) on zero-cost artifacts. Now, for the record, when toughness => damage a creature's taken since the last end-of-turn step, it goes straight to the discard pile, a.k.a. the graveyard. Yes, it's possible to animate artifacts only to kill them. Since any competitive Vintage deck will include a Black Lotus, a Lotus Petal, and all the appropriate Moxen for its colors, any competitive Vintage deck not including those will include Titania's Song or its aura (affects only one) cousin, Animate Artifact. Also, if Titania's Song is destroyed, though only two colors can really destroy it, And I Must Scream is invoked.
Lord of the Undead (a card which, among other things, can return zombies from the graveyard to your hand) + Lord of the Pit (a card which requires a sacrifice every turn or it does more damage to you). What sadist would play this? A sadist who wants to win, that's who.
The Stuffy Doll/Guilty Conscience combo is particularly terrifying. Essentially you kill your opponent by making a voodoo doll of him feel guilt, which damages the voodoo doll, which damages your opponent, which makes the voodoo doll feel guiltier, which damages the opponent more. You give a doll a conscience only so that it can kill your opponent with its own shame. Over killing your opponent.
A storyline-related one: New Phyrexia. The good news is, Phyrexians can't planeswalk, so unless they get something like the Weatherlight, they're safe. The bad news is, every plane Karn has ever visited before Venser purified him has Phyrexian oil on it! And so long as a drop of Phyrexian oil is on any plane, the Great Work can continue. And if the Mirrans with their affinity and Skullclamps and all the rest of their tricks couldn't beat the Phyrexians, what chance do (for instance) the Mercadians have?
Luckily, Karn's dealt with the issue by simply negating the oil's crazytime effects. Besides which, the Mirrans had the disadvantage of already being partly metal and therefore more vulnerable to phyresis.
The Innistrad block ends with Griselbrand dying and most of the demons being hunted down and killed. However, it was stated in "The Saint, the Geist, and the Angel" that Demons do not die permanently. Withengar, for example, returned after being defeated by st. Traft's guardian. What's to say that Griselbrand won't return? Also, there's no helvault to trap them in and it is never stated that angels can return from the dead. Eventually, the angels will slowly die off and the demons will just come back.
Given that the reason the demons can return is that they are in essence constructs of pure black mana, I'm pretty sure that angels (constructs of pure white mana) can also reincarnate.
On the other hand, it's sometimes stated that the chain veil could somehow kill Griselbrand permanently, so we may have seen the last of him.
The card Defy Death's flavor implies that angels can come back as well.
Even if Griselbrand does come back and somehow defeat Avacyn it wouldd just drag Sorin (the guy who ccreated Avacyn) back to Innistrad. And Sorin is NOT somebody you want mad at you.
Speaking of demons, Wordof God says that Ravenous Demon's design was based on the idea that to demons, humans are like potato chips.