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: Exile this creature. Return it to the battlefield under its owner's control at the beginning of the next end step.

: This creature can't be blocked this turn.

: This creature gets +1/-1 until end of turn.

: This creature gets -1/+1 until end of turn.
Aetherling's last ability can be activated even if its power is 0 or less. If a creature would assign 0 or less damage in combat, it doesn't assign combat damage at all.