// Other white creatures get +1/+1.
this.addAbility(new SimpleStaticAbility(Zone.BATTLEFIELD, new BoostAllEffect(1, 1, Duration.WhileOnBattlefield, filter1, true)));
// Nonwhite creatures get -1/-1.
this.addAbility(new SimpleStaticAbility(Zone.BATTLEFIELD, new BoostAllEffect(-1, -1, Duration.WhileOnBattlefield, filter2, false)));
// Pay 2 life: Return Crovax, Ascendant Hero to its owner's hand.
this.addAbility(new SimpleActivatedAbility(Zone.BATTLEFIELD, new ReturnToHandSourceEffect(true), new PayLifeCost(2)));
}