I think what I found most interesting about Thrillkiller wasn't the dark, gritty Batman take, but the fact that the initial series had Robin and Batgirl as the dynamic duo. She carried over into a followup one shot where Bruce Wayne then took the mantle of Batman.

Swapped out the lower legs for an MU Dagger to make her a bit taller. Head was from a BossFight blank with the hair and tips to the mask sculpted on. Sculpted on the sleeves and arm blades, bat wings on her boots, and her full utility belt. From there, a full repaint, and all done!