Diablo 4's post-credits scenes introduce potential new major villains.

Mephisto's return as a villain is teased in Diablo 4.

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The post-credits teasers feature a horned demon resembling Mephisto.

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Diablo, the Lord of Terror, may play a significant role in the game.

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There could be an alliance between Mephisto and Diablo.

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Inarius might transform into Diablo's version of Satan.

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Diablo 4 presents an opportunity for iconic characters to undergo a change of heart.

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