Darkness as tiefling ability cannot target an area or another character/npc or object. It can ONLY target my own character.
Darkness from assassin spellbook can ONLY target an area, not my own character.
Blindsight is supposed to make you immune to magical darkness, so in theory casting both Darkness and Blindsight on yourself should make you immune to the
concealment effect, i.e. melee opponents in your cloud of darkness are not concealed to you but you are concealed to them. Doesn't work. Even with Blindsight cast on my character, my character's opponents are still 20% concealed from my character.
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