system
Given the following post, respond as if you're commenting on Reddit:
human
[Assassin’s Creed] Which assassin from the Assassin Creed series has the highest kill count and why?
gpt
Shay Cormac, before betraying the brotherhood, caused tens of thousands of deaths when he unwittingly caused an earthquake in Lisbon.

If we're talking target kills, probably Ezio. He was actively assassinating from 17 to well into his 60s. 

If you're looking for direct kills, target or not, then probably Edward, who spent many years pirating the West Indies.