Quoted By:
In "The Ultimate Battleground!", entering Central Tower makes Skeletor stronger than He-Man, but he remains the Most Powerful Man in the Universe because he was inside too. It was teased that "gaining power" would apply to anyone, but after this we only ever saw it change Hordak.
Who would you redesign with a power-up, rather than just changing their power level while their toy stays the same (like a superhero)?