mutating onto a creature you don't control

[DirkGently]

Notably, mutate says a creature you OWN instead of control. I found that surprising.

What does this mean, if you mutate onto a creature your opponent has gained control of somehow? Do you gain control of it? Do you not gain control of it? Do you gain control of it only if you put the mutate creature on top? I kinda want to say the last thing is true, but that seems kind of absurd. I don't get why wotc templated it this way.

[void_nothing]

No, nothing in the text of mutate implies a control change. The mechanics article doesn't mention the issue at all; think of it like putting a beneficial Aura on a creature you don't control. Can you do it? Absolutely. There's just no reason to.

As for why? It's shorter than writing "own and control" in the reminder text and you'd simply never mutate a creature you didn't control anyhow.

[DirkGently]

But with an aura, you still control the aura. You control it while you cast it, you control it while it's on the battlefield, regardless who controls the creature. If that's true for mutate, and you put the mutate creature on top, then you control the permanent with the name "name of mutate creature", but you don't control the permanent which it is? That doesn't make any sense. Either the mutate creature switches control to your opponent when it resolves, or the whole creature switches sides of the battlefield when it resolves. I can't see any other way it'd make sense.

If you put the mutate creature underneath, then I'd be along for the ride saying it's still your opponents, since the creature which the permanent "is", is still the one your opponent controls.

What I don't understand is why it doesn't JUST say "that you control". Why does it matter who owns it?

[peteroupc]

The exact rules for mutate haven't been released yet. However, the mechanics article for Ikoria: Lair of Behemoths doesn't speak of "target non-Human creature you own and control" as opposed to just "target non-Human creature you own". But in general, questions that ask why one wording is used on a card rather than another (especially where one wording is alleged to be better) are questions that only Magic R&D can answer and are out of scope for this forum.

According to the mechanics article, a mutating creature spell doesn't enter the battlefield; rather, it merely changes a permanent's characteristics when it resolves. Thus, as far as the game is concerned, this results in only one mutated permanent on the battlefield, not several, even if multiple cards contribute to that permanent's appearance.

For example, if a mutating Huntmaster Liger targeting Grizzly Bears resolves, and you choose to put Huntmaster Liger on top of Grizzly Bears, Grizzly Bears will change certain characteristics; for example, its name will now be Huntmaster Liger, it will be white, it will be a Cat creature (not a Bear) and it will have the ability "Whenever this creature mutates, creatures you control get +X/+X until end of turn, where X is the number of times this creature has mutated". And this will happen no matter who controls Grizzly Bears at the moment. As with certain abilities found in Erhnam Djinn or Kukemssa Serpent, an effect can change the characteristics of a permanent an opponent controls just fine.

[DirkGently]

So if I'm understanding you correctly, you're saying that the different "parts" of the creature can have different controllers even if it's just one permanent? Or are you saying that, when you finish resolving the mutate ability on an opponents creature, it switches control to them since they still own the permanent it became a part of?

I guess I'm still not really sure what you're saying. It seems like you're saying there's only one permanent, but then I'm not sure what happens control-wise, something's gotta switch if there's only one permanent and you each control part of it.

Let's say I cast grizzly bears.
My opponent casts control magic on the grizzly bears.
I then mutate the grizzly bears with huntmaster liger and put the liger it on top.

I think there's only 4 possibilities. Which is correct?

1) I control the huntmaster liger creature, with my opponent still controlling the functionally useless grizzly bear "enchantment-type-thing" hanging off the bottom.
2) There is only one permanent, so my opponent controls the huntmaster liger in all its parts, so essentially I just donated the huntmaster liger card.
3) There is only one permanent, since the liger is the creature and I control the liger card, the whole creature is mind and I essentially just control-magicked back the creature.
4) My opponent controls the creature whose name just-so-happens to be huntmaster liger, but I control an "enchantment-type-thing" that's giving it the name huntmaster liger plus its stats and abilities.

Ugh I hate all of these tbh, they all seem so messy.

[peteroupc]

Based on what we know now, number 2 is the closest. If a mutating creature spell such as Huntmaster Liger resolves, it only changes certain characteristics on the creature it targets. The spell never changes control of that creature. After that, you can think of the spell in one of two ways:

• The spell "vanishes" for most purposes, as far as the game is concerned. Or...
• The spell is like a "marker" on the permanent (but not really a counter) that notes what the permanent looks like.

the card that represents that spell effectively becomes part of the resulting creature.
In any case, a player can't control only part of a permanent, rather, a player can control a permanent only as a whole.

EDIT (Apr. 12): Correctness edit in view of release notes and update bulletin.

[DirkGently]

Hmm, that is very confusing but maybe the simplest option? Still not sure why it isn't "control" but w/e. I guess we'll have to see when the comp rules come out, maybe then it will become clearer.