If the creature you put onto the battlefield is no longer on the battlefield or no longer a creature, the target creature won't deal or be dealt damage
Far more impactful and important to bear in mind when approaching your first game, is which bread and butter common cards other players are valuing the highest
You aren't an aggro deck so, rather than just throwing a ton of 4/4's in the opponent's face, the tempo deck's concern is laying down select threats in the early to mid game and protecting/disrupting your way to victory
So, the history of [casthaven]Savannah Lions[/casthaven]
And then there's a reprint of an ancient ($50!) land destruction spell, Ice Storm
Whenever another Goblin, Orc, or Army you control dies, exile the top card of your library