Valakut Exploration (Promo Pack) [Zendikar Rising Promos] Core Set 2021 Promos Hunting Grounds has "Whenever an

Hunting Grounds has "Whenever an opponent casts a spell

up to one target attacking creature gets +2/+0 and gains trample until end of turn

put a +1/+1 counter on it for each other Zombie that entered the battlefield under your control this turn

They come from breathing and simply noticing

Valakut Exploration (Promo Pack) [Zendikar Rising Promos] Core Set 2021 Promos Hunting Grounds has "Whenever anSet: Zendikar Rising Promos Type: Enchantment Rarity: Rare Cost: {2}{R} Landfall Whenever a land enters the battlefield under your control, exile the top card of your library. You may play that card for as long as it remains exiled. At the beginning of your end step, if there are cards exiled with Valakut Exploration, put them into their owner's graveyard, then Valakut Exploration deals that much damage to each opponent.