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- Sandu - A circus performer with limited extra-sensory powers which were enhanced by Loki.
- Seth - Egyptian God of Evil.
- Shatterfist - user of 'Power Gloves', member of Masters of Evil.
- Surtur - A fire demon native to the extradimensional plane of Asgard with power rivalling that of Odin.
Read more about this topic: List Of Thor Enemies