Super Turtles Dai Pinchi! Saint Tōjō!

"The Great Crisis of the Super Turtles! The Saint Appears!" (スーパータートルズ大ピンチ!セイント登場!, Sūpā Tātoruzu Dai Pinchi! Seinto Tōjō!) is the first episode of Mutant Turtles: Chōjin Densetsu Hen

Plot
The Turtles explored the temple of the lost Muta Kingdom where they met the spirit of light called Kris Mu, who was contained inside the Muta Stone. In reward, she gives the Turtles the ability to do the Super Mutation, which turns them from regular turtles into Super Turtles for three minutes. When all four Super Turtles turns into one, they turn into the all-mighty Turtle Saint. At the same time, Shredder and Krang manage to find the Dark Muta Rock as they try to awake the demoness Dark Mu contained inside the crystal.