Today Square Enix is celebrating the 20th anniversary of the Kingdom Hearts franchise. The original Kingdom Hearts arrived on PlayStation 2 on March 28, 2002, so today's anniversary celebration is a few days late. Fans likely won't mind, considering Square Enix has taken the opportunity to announce Kingdom Hearts 4, as well some side projects. In their excitement, Kingdom Hearts fans have found several topics to focus on, one of which is the Disney villain Hades.

Several Kingdom Hearts-related terms are currently trending on social media. #KingdomHearts20thAnniversary is the most popular. Quadratum, the city in which the new Kingdom Hearts 4 trailer takes place, is another. AT-ST, KH 3, and several others are also making appearances. Hades, however, is unique and especially exciting. That's because Hades was the tease that the Kingdom Hearts 4 trailer ended on. Hades is the topic that Kingdom Hearts fans are using to speculate on what the new game's story will be about.

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The Kingdom Hearts 4 trailer ended with Donald and Goofy searching for someone that they think might be able to help them. The target of their search is unclear, as is their overarching goal. As they walk through the pitch dark guided by Donald's glowing wand, a blue light appears behind the pair. Hades' voice rings out, "Hey, just where do you think you're going?" Donald and Goofy turn to see an off-screen fire blaze, frightening them. That's where the trailer ends.

It's clear that Hades, the villain of the Disney film Hercules and longtime antagonist in the Kingdom Hearts games, has a role to play in Kingdom Hearts 4. But there are a number of questions that pop up due to his inclusion in the new trailer. Fans question whether Hades is who Donald and Goofy are looking for, and why they'd do that. Hades could also be standing in the way of Goofy and Donald, preventing them from finding who they're looking for, too.

The last time Kingdom Hearts fans saw Hades, he was defeated with relative ease by the joined forces of Sora, Donald, Goofy, Hercules, and Zeus. Hades is trying to take over Olympus with the power of the Titans but is otherwise uninvolved in Kingdom Hearts 3's overarching story. Regardless, he's a fan-favorite antagonist, and there's hope he has a larger role in Kingdom Hearts 4.

That Square Enix would choose to end its Kingdom Hearts 4 trailer with a Hades tease is perhaps indicative of how much faith the company has in him as a villain. Square Enix clearly believes just teasing Hades' voice will be enough to get fans excited for more Kingdom Hearts. That definitely implies Hades will be a featured character in Kingdom Hearts 4, but fans may have to wait a while yet to find out more.

Kingdom Hearts 4 is in development.

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