Imrae (5e Equipment)
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Wondrous Item (arcane focus), Legendary (requires attunement by a spellcaster)
Imrae is an ovular black opal of such uncommon darkness that it can be transfixing, and a passing observer might find themselves staring at it without even realizing. Tendrils of purple reach and writhe across and through the stone, seeming to move like living ink dropped in liquid...but so slowly you're not sure if it's moving at all. Most strangely, however, is that the smarter someone is, the more they might find themselves drawn to this stone, with a character of 16 intelligence or higher being unable to stop themselves from reaching for it. Characters with an intelligence of 18 or higher will do anything in their power to possess the stone, including violating their moral alignment to do so. If Imrae is already attuned, the stone will stop drawing others to it. Once Imrae is attuned, the user will do anything to keep it close to them until they are subsumed entirely.
Champion's Choosing Any spellcaster can attempt to attune themselves to Imrae, but the DM will decide if she accepts or rejects the spellcaster. If she accepts them, Imrae becomes the spellcaster's arcane focus and begins to take over their mind and personality. If she rejects them, she does 2d6 necrotic damage and steals all memory of how they obtained the focus, as well as easily reachable magical knowledge. However, they will no longer be drawn by the compulsion of the stone. If a rejected spellcaster tries three or more times to attune to Imrae, she will begin eating their spells slots on each try, adding 1d6 of necrotic damage, stacking, as well.
Consumption Once attuned, Imrae begins to take over every aspects of the wielder's personality, starting with a hunger for knowledge, especially arcane, and will begin to make the user favor more necromantic and darker fields of magic. The wielder may become erratic, suspicious, and will begin to conduct arcane research with the greatest possible secrecy. The further the wielder goes in study of aberrations, necromancy, and the other dark arts Imrae will push them to, the more they become lost and Imrae will take over, until the wielder is no more than a host for the sentience of Imrae herself.
Arcane Addiction If a third party attempts to separate the wielder from the focus, the wielder will become increasingly violent until they begin attacking anyone and anything they see with no concern of physical safety. If the process is caught early enough and the wielder can be restrained for the duration of the madness, reason can be brought back to the spellcaster. The attunement would be removed automatically, and as long as the spellcaster no longer sees or comes into contact with Imrae then the process can stay reversed. However, if the spellcaster once more sees Imrae they will do anything in their power to get to it - upon touching it, the process is resumed and in fact sped up.