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We are playing Storm Kings Thunder and our party picked up a Fire Giant Sword.
Can we polymorph our fighter into a Giant Ape in order to wield the sword, and could he benefit from multiattack or battle master maneuvers?
It looks like in the text of polymorph suggests that he may not even be able to wield the sword:
The creature is limited in the actions it can perform by the nature of its new form, and it can't speak, cast Spells, or take any other action that requires hands or Speech.