this.color.setBlack(true);
this.power = new MageInt(5);
this.toughness = new MageInt(5);
// Grimgrin, Corpse-Born enters the battlefield tapped and doesn't untap during your untap step.
this.addAbility(new EntersBattlefieldTappedAbility());
this.addAbility(new SimpleStaticAbility(Zone.BATTLEFIELD, new SkipUntapSourceEffect()));
// Sacrifice another creature: Untap Grimgrin and put a +1/+1 counter on it.
SimpleActivatedAbility ability = new SimpleActivatedAbility(Zone.BATTLEFIELD, new UntapSourceEffect(),
new SacrificeTargetCost(new TargetControlledCreaturePermanent(1, 1, filter, false)));
ability.addEffect(new AddCountersSourceEffect(CounterType.P1P1.createInstance()));