[
    new MagicWhenOtherSpellIsCastTrigger() {
        @Override
        public boolean accept(final MagicPermanent permanent, final MagicCardOnStack spell) {
            return spell.hasSubType(MagicSubType.Giant);
        }
        @Override
        public MagicEvent executeTrigger(final MagicGame game, final MagicPermanent permanent, final MagicCardOnStack cardOnStack) {
            new MagicEvent(
                permanent,
                new MagicSimpleMayChoice(
                    MagicSimpleMayChoice.ADD_PLUSONE_COUNTER,
                    1,
                    MagicSimpleMayChoice.DEFAULT_YES
                ),
                this,
                "PN may\$ put a +1/+1 counter on SN."
            );
        }

        @Override
        public void executeEvent(final MagicGame game, final MagicEvent event) {
            if (event.isYes()) {
                game.doAction(new MagicChangeCountersAction(
                    event.getPermanent(),
                    MagicCounterType.PlusOne,
                    1,
                    true
                ));
            }
        }
    }
]