this.power = new MageInt(2);
this.toughness = new MageInt(4);
// Whenever Ubul Sar Gatekeepers enters the battlefield, if you control two or more Gates, target creature an opponent controls gets -2/-2 until end of turn.
Ability ability = new ConditionalTriggeredAbility(
new EntersBattlefieldTriggeredAbility(new AddCountersTargetEffect(CounterType.M1M1.createInstance(2))),
new PermanentsOnTheBattlefieldCondition(filter, PermanentsOnTheBattlefieldCondition.CountType.MORE_THAN, 1),
"Whenever {this} enters the battlefield, if you control two or more Gates, target creature an opponent controls gets -2/-2 until end of turn.");
Target target = new TargetCreaturePermanent(targetFilter);
ability.addTarget(target);
this.addAbility(ability);