Cook

Cook (料理人) is the Unique Skill that Shion obtained after Rimuru's Harvest Festival.

Sub-Skills

 * Certain Outcome (確定結果): A heinous ability that directly alters the laws of the world, similar to an Ultimate Skill. It allows the user to freely change the result of an action or the state of an object into their desired outcome, no matter how improbable. It is possible to permanently alter the status of a living being or object to make an unnatural state their natural state, which makes any form of healing useless. The only way to counter this is to also be able to manipulate the laws of the world such as via Law Manipulation or an Ultimate Skill and then manage to overcome the user's will with their own will.
 * Optimal Action (最適行動): Allows the user determine the best course of action in a given situation by allowing them to see through the flow of their movements. It also enables the user to perfectly recreate anything they've done once, for instance as long as they have scratched an enemy they can make their attacks always deal damage; or if they've defeated an enemy once, no matter how difficult, they can defeat them again with ease.

Related Arts

 * Chaotic Fate (天地活殺崩誕): Combination of Certain Outcome and Optimal Action. It allows Shion to manifest her desired reality while maximizing her chances of success in any given situation.

Trivia

 * When Shion was undergoing her Artificial Harvest Festival, Ciel stopped this skill from becoming an Ultimate Skill, deeming its evolution to be a potential threat to Rimuru.