// At the beginning of your upkeep, you may have target creature you control get +X/+X until end of turn,
// where X is the number of creatures you control. If you do, sacrifice that creature at the beginning of the next end step.
PermanentsOnBattlefieldCount amount = new PermanentsOnBattlefieldCount(new FilterControlledCreaturePermanent());
Ability ability = new BeginningOfUpkeepTriggeredAbility(new BoostTargetEffect(amount, amount, Duration.EndOfTurn), TargetController.YOU, true);
ability.addTarget(new TargetControlledCreaturePermanent());
ability.addEffect(new JunkyoBellSacrificeEffect());
this.addAbility(ability);
}
public JunkyoBell(final JunkyoBell card) {