All Bonus Character and Custom Character weapons, and all Bonus Characters (as far as I know). Part 1 is Standard Character weapons with a few "the ancient" weapons missing.
There is one character from SC2 that is in this game but I haven't unlocked him yet if he is playable, which he should be, but there is no slot for him in the Standard Character squares. Only place for him is in Bonus Characters, and there are no available (locked) weapons to purchase for him. I forget his name, in SC2 he was big like Astaroth, but in SC3 he is smaller and uses a lance.
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