My playthrough was a Githyanki necromancer. I'm playing AD&D 2e, so I knew my way through the world and Githyanki protocol. But, since I didn't want spoilers and didn't read any guides, I had zero meta-knowledge of the game or the story, so I was making up and changing the head canon as we went. My Tav - Sava, see profile pic - hails from a less glamorous crèche than Lae'zel and wound up being the apprentice of a powerful Sa'varsh who unfortunately fell into disfavour with the lich queen and fought quite desperately to win it back. Sava was therefore often wandering the edges of Elturgard, mingling with smugglers and gathering supplies and information for dark experiments. Eventually, Sava was sold to Balthazar who already had stakes in the operation. [
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Sava was in a difficult position. Being a necromancer would have put her into a position next to a Kith'rak, but since she never made the degree none of this was official. Instead, she had to accept Tir'su lessons from a hyper-aggressive fighter who was half her age and hide her identity from Kith'rak Voss who may have had reasons to kill her even before they got tadpoled. Up until the final chapter of Act III, Sava was the commander of her adopted unit, trying to keep everyone alive, while the road completed her training as a necromancer.