[
    new MagicWhenYouCastSpiritOrArcaneTrigger() {
        @Override
        public MagicEvent executeTrigger(final MagicGame game,final MagicPermanent permanent,final MagicCardOnStack spell) {
            return new MagicEvent(
                permanent,
                this,
                "SN gains forestwalk until end of turn."
            );
        }
        @Override
        public void executeEvent(final MagicGame game, final MagicEvent event) {
            game.doAction(new MagicGainAbilityAction(event.getPermanent(),MagicAbility.Forestwalk));
        }
    }
]