Whenever another creature you control with power 2 or less enters, this creature gains flying until end of turn.
Marketwatch Phantom's ability checks the power of a creature only at the moment it enters the battlefield. If it enters with counters, those counters are included. If that creature's power is 2 or less when it enters the battlefield but becomes greater than 2 after the ability triggers, Marketwatch Phantom will still gain flying until end of turn.
