Dream Chisel + Primordial Mist + Planar Gate

Dream Chisel

Primordial Mist

Planar Gate

How it works

1. Cast the creature with morph or megamorph for its morph or megamorph cost by paying 0, putting it on the battlefield face-down as a 2/2 creature.
2. Activate Primordial Mist by exiling the face-down creature face-up, allowing you to cast it from exile this turn.
3. Repeat.