Mythril Souls are the mob drops obtained from killing most mobs that are native of the Mythril Mountains. The main use of Mythril Souls is the crafting of the Base Spawner Crystal, which are then used to make different Boss Spawner Cystals. Mythril Souls can also be placed in a crafting sqaure to produce Mythril Fragments, which is the best method to farm Mythril Fragments. As well souls can be used to craft blocks using the crafting table. The blocks you craft can be used to create potals to different dimensions.
Mythril Souls can be obtained by doing any of the following: