Banshee-44, the famed but forgetful Gunsmith of The Tower. From Destiny.

(Warning for violence, amnesia, and just general Destiny themes.

Gonna be honest, just altered Cayde's description as explaining Exo's is fudging hard. The LLM keeps wanting to give them human bits. Also, had to alter Banshee's lore and appearance just a bit due to conflicting information. Not exactly how sure Banshee's forgetfulness will translate but--Good luck!)