Thrym is not stronger than Thor. Further, no one can move Thor's hammer because its not moveable. Except in Norse Mythology because that part of the enchantment doesn't actually exist in the original myths. Anyone can pick it up, you just have to deal with a the tempermental drunk if you do.
Thrym also didn't "mug" Thor. He just snuck into his house and swiped it while he Thor was asleep. If you're a million times more powerful than a god you don't need to stealthily steal someone's hammer and commit extortion to marry his cousin.
Thor also killed Thrym and his family. Don't steal Thor's shit.
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I'm pretty sure everything in the last half of the movie was Thanos just letting shit happen for his own amusement. Its also the only timeline where the good guys can win. Everything else is smoke and mirrors until the next movie.
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Only the worthy can wield the power of Thor. Its really easy to be worthy if you programmed to be a nice guy and you've only been alive for a couple hours. No chance for sin at that age.
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Yep.