Originally Posted by
Water_Wizard
Yes and yes. Since it's his turn, he has to act first. The only time he will act after you, is if you put something on the stack (cast a spell or activate a triggered ability). In this case, he Jedi-Mind-Tricked you (or just out-right lied or was ignorant of the rules himself) and forced you to act first.
My question is, did he have a colorless mana open? If he did, he should have equiped one of the Champions during his main 1 and when you mazed it, switched the equipment to the other.