Ryukka Hunter

Stalk (When this creature would enter the battlefield,
it enters the battlefield face down as a 2/2 creature.
When an opponent's creature enters the battlefield,
turn this face up, then those two creatures fight.)
When Ryukka Hunter is turned face up, if the creature it stalked had a power greater than it,
Ryukka Hunter gains +1/+0 until end of turn.