Iggwilv
Iggwilv, also known as Natasha or simply Tasha, is a malevolent archmage originating from the Greyhawk setting, first mooted in 1975 in the Tsojconth tourney in WinterCon V Detroit (Rock City). She belongs to that small, elite club who represent characters originally played by Gygax and his buddies during the founding of Dungeons & Dragons, such as Murlynd, Zagyg and Mordenkainen. She was male in 1975; retconned female in 1982 because that let her spawn children like "Tsojconth"'s vampiress, and to get funky with demons. (Not that Graz'zt had much of a preference himself.)
Iggy's in-game lore is that she adventured with the OGs, learning much about magic in the process, but ultimately revealed herself as evil and betrayed them, going on to become one of the Great Wheel's foremost experts on black magic and demonology. So much so that Dragon Magazine titled its articles on various demons and Demon Princes as "The Demonomicon of Iggwilv", after a literal book she wrote on the subject. She later got a sourcebook named after her in 5E. She is one of the most powerful people in the multiverse, strong enough that she can beat Mordenkainen in a straight fight, and she also kicks his ass at chess, as shown in the gallery below.
It was rumored that she may be a daughter of Baba Yaga. This was later confirmed, but it was revealed she was adopted instead of being biologically related.
About a century before the Guide to the World of Greyhawk 576 CY, so 480ish, Iggwilv conquered Perrenland and looted the place for her demonological research - for instance, imprisoning the Demon Prince Graz'zt, for her personal manservant and boytoy. A decade later Graz'zt got free, and in the process of banishing him back home, Iggwilv's coterie betrayed her and looted "her" (mostly Perren) wealth. Perrenland freed itself immediately afterward. It was later ruled that she, definitively XX now, survived.
(Literal) Legacy
A daughter, who guards her vault under The Lost Caverns of Tsojcanth in eternity as a vampire, is (or was) Drelnza. This one was born human. We're not told if she was born before the Perrenland adventure and Graz'zt sexytimes, or afterwards; but since the "vampiress" is in the "Tsojconth" original, before is more likely.
From The Ashes further established Iggwilv for the maternity of the cambion Iuz, who'd later ascend to an actual god on their homeworld of Greyhawk. She whelped him when she kept Graz'zt bound. He later repaid the favor by keeping her as his slave. She and Graz'zt are currently in mutual tsundere with one another, genuinely loving one another to the extent that either being is capable of love, but also too selfish and depraved to express it in any way a sane mind would call healthy.
5th Edition
Spoilers for a recent adventure
