So, I was asked at the Indy summit about this item, I think it came up at other summits too. We have a hotfix coming that will address this issue. For those that don’t know, the issue is that the crystal buffs mind, but we don’t have mind in the game anymore.
When the Hotfix rolls out, what should happen is, if the crystal is in your inventory it will convert itself to a newer version. If the crystal is not in your inventory, just pick it up and use the radial menu, it will auto-update itself to the new version then.
Currently the crystal will give you an Action buff, with a damage proc. The proc is a percentage chance to do extra damage when you attack.