Yeah, my hypothesis seems more likely now. Argo the past blacksmith friends are aligning to be the big bads with azurite crystals. Wonder what the catalyst was for him to go demon lord and kill a hero was. It was odd to see Lerius' form change to something similar to the azurite bads, but it makes sense if it was a blacksmith's ability.

Welp there is past the ice swordsman hero. (still wondering if the tamer will also show up, or if her dog was the only sign of her)
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I wonder if the past heros got corrupted forcing the blacksmith to end them, or if they died and he tried to remake them to bring his friends back.