Editing Ikoria (section)

==Mechanics and Themes==
* ''Mutate:'' The newest and weirdest mechanic in the set, and the feature teased by Mark Rosewater to be the "craziest mechanic in Magic history". When you cast a creature with Mutate, you can have them appear on the battlefield as a regular creature, or if you pay the cost, you can have it enter as a mutation. When you cast a creature as a mutation, you put that card on top of, or on the bottom of another non-human creature. A mutated creature has the stat block of whatever is on top, plus whatever was in the textbox of the creature on the bottom. If a creature is on the stack ready to mutate, and the creature it was going to mutate would die, you still get the card that was on the stack. You can mutate a creature as many times as you want.
* ''Companion:'' A sort of pseudo-commander in a standard set. When you have a card with companion, and you meet the conditions that the card has, you can declare that creature as your Companion. <s>You can then cast it from your sideboard</s> and once it is in the game, it acts as if was always in your deck. It goes to the graveyard on death, can get exiled, etc. If you want, you can completely ignore the Companion part of the card, and put it in your deck as normal. Since release, the Companion cards have made quite the splash in many constructed formats, with many people calling for a mass banning of the companion cards. Rather than Ban the whole mechanic, WotC changed the mechanic so if you have a designated companion in your sideboard, you can pay 3 generic mana to add it to your hand (and are no longer able to cast it directly from your sideboard).
* ''Keyword Counters:'' Simply put, certain spells on Ikoria can put Keyword Counters on creatures. This works just like +1/+1 counters, but it's abilities instead.
* ''Cycling:'' A much-beloved limited mechanic is coming back. Don't like a card in your hand? Cycle it and get something new.
* ''Odd or Even:'' Many cards in the set have you choose even or odd when they come onto the battlefield, or otherwise care about whether a spell has an even or odd CMC. Remember, 0 is considered an even number.