Collect 300+ different items. All 300+ items do not have to be in your inventory at the same time. As long as you have the item recorded in your Item Compendium, you don't have to keep it. Items, weapons, shields, spells, sub-weapons, Martial Arts, armor, etc. all count towards this. Each character has specific weapons or spells that can only be obtained by that character, so be sure to play as each one. The trophy should unlock somewhere around 320 items or so.
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