this.color.setBlue(true);
this.power = new MageInt(2);
this.toughness = new MageInt(1);
// Whenever you cast a spell that's both blue and red, Riverfall Mimic has base power and toughness 3/3 until end of turn and can't be blocked this turn.
Ability ability = new SpellCastControllerTriggeredAbility(new SetPowerToughnessSourceEffect(3, 3, Duration.EndOfTurn), filter, false, rule);
ability.addEffect(new GainAbilitySourceEffect(new UnblockableAbility(), Duration.EndOfTurn, false, true));
this.addAbility(ability);
}