In the Spider-Man: No Way Home trailer, Doctor Strange acts recklessly with his spells, and it's proving Mordo right. The first teaser for Spider-Man: No Way Home revealed an overview of the upcoming Marvel Cinematic Universe film. In Spider-Man: Far From Home, Mysterio (Jake Gyllenhaal) reveals Spider-Man's (Tom Holland) identity, making life hard for Peter Parker. So in the new movie, Parker goes to Doctor Strange (Benedict Cumberbatch) to rectify the situation, and the Sorcerer Supreme's solution is making everyone forget that Parker is Spider-Man. However, while Strange tries to cast the memory wipe spell, Parker interferes, saying he doesn't want everyone to forget him after all. The disruption changes the spell and releases the Multiverse.

The trailer teases that Strange's spell allows several past Spidey villains to return. In the trailer, Alfred Molina's Doc Ock, an antagonist from Sam Raimi's Spider-Man 2, makes a surprising appearance. "Hello, Peter," Doc Ock says after stepping into the scene. Willem Dafoe's signature laugh and a Pumpkin Bomb also hint at Green Goblin's return. Brief moments reveal other villains, including Jamie Foxx's Electro and Thomas Haden Church's Sandman, may also make a comeback. And some fans are even theorizing that the film could introduce Mephisto.

Related: Spider-Man: No Way Home - Every Marvel Villain Teased By The Trailer

With his recklessness in the trailer, Strange is proving Mordo (Chiwetel Ejiofor) right. In Doctor Strange, Cumberbatch's character traps Dormammu in a time loop to defeat the monster from the Dark Dimension. Strange manipulates space and time to take down Dormammu, causing Mordo, Strange's former friend, to abandon him after the battle. Mordo is against anyone messing with the natural law, and he reprimands Strange for thinking there won't be consequences to messing with time. He says ominously, "The bill comes due. Always!" Mordo then takes a villainous turn. He makes it his mission to remove other sorcerers from the world, thinking too many people are careless with magic. However, Strange isn't doing anything to show he's wrong.

Doctor Strange and Baron Mordo

Because Strange messes with natural law again in the No Way Home trailer, Mordo's warning comes true. Before Strange casts the memory wipe spell in the trailer, Wong (Benedict Wong) even warns him against it. "Don't cast that spell. It's too dangerous," Wong says. Strange says he won't, and then he gives Parker a wink. However, things clearly don't go as planned. By manipulating the natural law, Strange opens up a wormhole to the Multiverse. Mordo turned his back on Strange for a reason, and the Sorcerer Supreme should've heeded his words.

Strange's spell raises big MCU questions. Considering Strange and the Avengers only recently helped stop Thanos (Josh Brolin) from destroying half of life in the universe, it seems the Sorcerer Supreme would be cautious over spells that could cause the end of the world. Yet, in the Spider-Man: No Way Home trailer, Strange seems uncharacteristically rash. He ignores Mordo's past warning and tries to erase millions of memories simply because Parker is having a hard time. The Sorcerer Supreme's behavior is so bizarre that it's even caused fan theories that a variant of Strange is the one casting the spell. Regardless, as Mordo said, the bill is coming due. And whether he's a variant or not, Strange has to pay for it.

More: Why Spider-Man Needs Doctor Strange In No Way Home (Not Just Multiverse)

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