[
    new MagicWhenAttacksTrigger() {
        @Override
        public MagicEvent executeTrigger(final MagicGame game,final MagicPermanent permanent,final MagicPermanent creature) {
            return (permanent==creature) ?
                new MagicEvent(
                    permanent,
                    this,
                    "Destroy all creatures other than SN."
                ) :
                MagicEvent.NONE;
        }
        @Override
        public void executeEvent(final MagicGame game, final MagicEvent event) {
            final MagicPermanent permanent=event.getPermanent();
            final MagicTargetFilter<MagicPermanent> targetFilter =
                    new MagicOtherPermanentTargetFilter(
                    MagicTargetFilter.TARGET_CREATURE,permanent);
            final Collection<MagicPermanent> targets=
                game.filterPermanents(permanent.getController(),targetFilter);
            game.doAction(new MagicDestroyAction(targets));
        }
    }
]