Fate is but a Probability Higher than Average

Kiritsugu was given the perfect artefact to summon the strongest Servant in the Caster class, but he wasn't entirely ready for who appeared in front of him. / Tokiomi was left wondering about the identity of the Archer answering him in the place of the Heroic Spirit he sought. At least he seemed dedicated to protect his daughter. AU Fate/Zero, AU Caster, Archer x Rin