Conditions: Thor and Cap angrily turn on Captain Marvel on the Endgame battlefield. Danvers is bloodlusted and calls on a cosmic warrior to fight with her: Thena. Who wins in a battle to the death? What-if feats don't count unless they are specific to how someone's powers work (e.g. Carol's energy absorption or Thor's control over his hammer).
Captain Marvel and Thena:
Thor and Cap: