The Mask: Animated Series (1995)

S1E15 Split Personality

During Walter's effort to reclaim the Mask, it shatters into two pieces. As a result, both Stanley and the Mask coexist simultaneously. Meanwhile, Chet Bozzack, an old high school tormentor of Stanley's, comes across the other half of the Mask and decides to wear it. This twist sets the stage for chaos as both halves of the Mask's power manifest in unexpected ways.