Shiki from Kara no Kyoukai, Kiritsugu and Kirei from Fate series.
Mindset: Serious; in character
Knowledge: Everyone knows about each other's powers
Base Shiki with Kanesada Kuji.
Kiritisugu starts with 56 Origin Bullets, he doesn't have an Avalon (it's useless anyways).
Kirei starts with 20 Black Keys and unlimited number of Command Spells.
Win by death/KO.