Debo Yanasanta and his brothers had created copies of Deboth to attack the world.
Sledge had found the six eggs of the late Greenzilla after surviving the crash and then hid the eggs in Hawaii, Japan, and China before they hatch. But the six Greenzillas were destroyed by the ten Dino Charge Rangers. It has no connections to Heximas.
Had evolved into a humanoid form after absorbing enough of the emotions to fuel his power.
Did not evolve into any other form what so ever.
His prehistoric form was naturally giant, but was shrunken to normal size at one point. His final form was naturally normal sized.