Activate Thermopod's second ability by sacrificing Dog Walker, adding ({R} magic symbol) .
When Dog Walker dies, Missy's first ability triggers, returning Dog Walker from your graveyard to the battlefield face down as a 2/2 Cyberman artifact creature.
Activate Dog Walker's disguise ability by paying ({RW} magic symbol) ({RW} magic symbol) , turning it face up.
Dog Walker triggers, creating two 1/1 Dog creature tokens.
Activate Thermopod's second ability by sacrificing a Dog, adding ({R} magic symbol) .