the dog has the ability to pounce off walls or can even stay on sigma.. and sigma could use a platform of his own (one of his giant "parts")
the dog is capable also of generating projectiles.. imagine sigma using a giant attack covering most of the cave space and the dog shooting projectiles in the rest

is it a valid move for sigma to deliberately destroy/collapse the entire cavern or erupt the lava and leave or sustain himself in wireframe form?