It's obvious who will win

Gumby is one of the most powerful fictional characters of all time
First of all, his strength is very immense. In the first ever episode "Moon Trip", He managed to push the moon's crust with ease to escape the hostile creatures. The Moon's mass is approximately 8.1 x 10^19 tons, meaning Gumby's strength is much greater than that to have him push it with ease. Second, he can never truly die. In the movie, he battles an evil robot clone of him created by the blockheads in a lightsaber duel. The robot Gumby manages to cut him apart with the lightsaber, but he instead splits into multiple smaller Gumbys. He also gets melted by fire in some episodes, but manages to pop right back into shape. Third, Gumby's shapeshifting prowess is fantastical. He can stretch very far, turn very giant, and shrink himself down. This means his is versatile in multiple scenarios, including ones that involve him having to take on a big enemy or something. I rest my case