Godzilla starts out as a theropod similar to the Godzillasaurus, and then mutates into Godzilla after exposure to an A-Bomb testing.

Out of all the Reiwa Godzillas, this is probably the most "vanilla" of them in that he doesn't have that many new abilities (Atomic Breath, regeneration, able to survive crushing depths, and amphibious lifestyle). However, what is new about him is that Godzilla's Atomic Breath charges up by having his dorsal fins extend from his body starting from his tail up his spine, and then they retract and his Atomic Breath is basically the Independence Day laser in that it can level an entire city in one shot, though it actually hurts him as a result. His regeneration is now on-par with Deadpool in that, even if he's blown to bits, if there's so much as one piece of him remains, he'll regenerate into his full body.

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The new trailer gave away the new atomic ray powerup, so nothing new there. Everything else is new for sure, and I'm assuming this is coming from people who've seen the film by now.

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Saw it last night, I can confirm it's accurate. But there’s more to the movie.