Abereth, Varian Adventurer v2

Creatures on the battlefield and in graveyards lose changeling and can't have or gain changeling.
Whenever a creature enters the battlefield, Abereth explores for each creature type that creature has that it doesn't share with creatures on the battlefield or in the graveyard.
Creatures you control have "{w}, {t}: this creature loses all keyword abilities until end of turn, then target creature you control gains each keyword ability lost this way until end of turn."