// Raging Ravine enters the battlefield tapped.
this.addAbility(new EntersBattlefieldTappedAbility());
// Tap: Add Red or Green to your mana pool.
this.addAbility(new GreenManaAbility());
this.addAbility(new RedManaAbility());
Effect effect = new BecomesCreatureSourceEffect(new RagingRavineToken(), "land", Duration.EndOfTurn);
effect.setText("Until end of turn, {this} becomes a 3/3 red and green Elemental creature");
// {2}{R}{G}: Until end of turn, Raging Ravine becomes a 3/3 red and green Elemental creature with "Whenever this creature attacks, put a +1/+1 counter on it." It's still a land.
Ability ability = new SimpleActivatedAbility(Zone.BATTLEFIELD, effect, new ManaCostsImpl("{2}{R}{G}"));
effect = new GainAbilitySourceEffect(new AttacksTriggeredAbility(new AddCountersSourceEffect(CounterType.P1P1.createInstance()), false), Duration.EndOfTurn);