Is playing a creature a spell in magic cards?
They are Creature Permanents while on the battlefield, Creature
Spells while being cast on the stack, and Creature Cards at any
other time. So when a player pays the mana cost on a creature card,
putting it on the stack, it is now a spell and can be countered by
anything that counters spells. After the spell resolves, it is just
simply a Creature Permanent.