// {tap}: Add {1} to your mana pool.
this.addAbility(new ColorlessManaAbility());
// As long as Riftstone Portal is in your graveyard, lands you control have "{tap}: Add {G} or {W} to your mana pool."
ContinuousEffect effect = new GainAbilityControlledEffect(new GreenManaAbility(),
Duration.WhileOnBattlefield, new FilterControlledLandPermanent());
effect.setText("As long as Riftstone Portal is in your graveyard, lands you control have \"{tap}: Add {G} or {W} to your mana pool.\"");
Ability ability = new SimpleStaticAbility(Zone.GRAVEYARD, effect);
effect = new GainAbilityControlledEffect(new WhiteManaAbility(),
Duration.WhileOnBattlefield, new FilterControlledLandPermanent());
effect.setText("");
ability.addEffect(effect);
this.addAbility(ability);
}