this.addAbility(new HideawayAbility(this));
// {tap}: Add {W} to your mana pool.
this.addAbility(new WhiteManaAbility());
// {W}, {tap}: You may play the exiled card without paying its mana cost if you attacked with three or more creatures this turn.
Ability ability = new ActivateIfConditionActivatedAbility(
Zone.BATTLEFIELD, new HideawayPlayEffect(), new ManaCostsImpl("{W}"), WindbriskHeightsAttackersCondition.getInstance());
ability.addCost(new TapSourceCost());
this.addAbility(ability);
this.addWatcher(new PlayerAttackedWatcher());