Whenever this creature attacks, you may have the base power and toughness of another target creature you control become X/X until end of turn, where X is this creature's power.
3GU: Adapt 3. (If this creature has no +1/+1 counters on it, put three +1/+1 counters on it.)
You can always activate an ability that will cause a creature to adapt. As that ability resolves, if the creature has a +1/+1 counter on it for any reason, you simply won't put any +1/+1 counters on it.
2024-02-02
wotc
Unruly Krasis's second ability will overwrite any previous effects that set the creature's power and toughness to specific numbers. Effects that otherwise modify its power and toughness will still apply no matter when they took effect. The same is true for +1/+1 counters.
2024-02-02
wotc
The value of X is determined only once, as Unruly Krasis's second ability resolves. Further changes to Unruly Krasis's power that turn won't cause the target creature's base power and toughness to change.
2024-02-02
wotc
If a creature somehow loses all of its +1/+1 counters, it can adapt again and get more +1/+1 counters.