Guild Wars 2

These are some title suggestions

When you achieve all slayer achievements.
Title: “Master slayer of Tyria”

When you achieve Weapon Master achievements.
Title: “Weapon Master of Tyria”

EDIT: Idea of these titles is to make slayer/weapon achievements more attractive.

You already get “Slayer” and “champion Slayer” from pvp. you can even get “Reaper” if you wanted to.

The weapon master one sounds ok, though.