Tempest Hart
{3}{G}Creature — Elemental Elk
Trample
Whenever you cast a spell with mana value 5 or greater, put a +1/+1 counter on this creature.
Tempest Hart // Scan the Clouds
{3}{G} // {1}{U}
Creature — Elemental Elk // Instant — Adventure
Oracle Text
Scan the Clouds
{1}{U}Instant — Adventure
Draw two cards, then discard two cards. (Then exile this card. You may cast the creature later from exile.)
Watch Out
Cast trigger fires even if counteredWatch Out
This triggers when the spell is cast, before it resolves. Even if the spell is countered, the cast trigger still resolves. Copies of spells are not cast, so they won't trigger this.