// When Goblin Pyromancer enters the battlefield, Goblin creatures get +3/+0 until end of turn.
this.addAbility(new EntersBattlefieldTriggeredAbility(new BoostControlledEffect(3, 0, Duration.EndOfTurn, filterCreature)));
// At the beginning of the end step, destroy all Goblins.
this.addAbility(new BeginningOfEndStepTriggeredAbility(new DestroyAllEffect(filterPermanent, false), TargetController.ANY, false));
}