What is a Contingency Contract?

In C.C., players can run two unique operations: one that is available every day during the current season (Permanent Site) with a fixed set of Contracts and another that is rotated daily during the current season (Rotating Site) with a different set of Contracts in each rotation. Before playing C.C. operations, the player can select the Contracts to use, which will alter the gameplay by buffing enemies, debuffing friendlies, and/or imposing various limitations; similar to the conditions of Challenge Mode, but with a combination of multiple handicaps up to the player's choice.

C.C. operations can be extremely difficult to clear even with high-level, high-rarity Operators, so to compensate this, all C.C. operations do not consume any Sanity.png Sanity, however they are not counted towards completing regular missions and do not give out Credit.png Credit if the player uses a Support Unit. Therefore, it is recommended to try C.C. operations as many times as possible until a solid strategy is found.

In addition, C.C. operations' result remains the same no matter how many Life Points the player have left (unless when using the Objective: Last Line of Defense contract which reduces Life Point to 1), thus it is sometimes better to let one or two enemies through on C.C. operations if victory is to be assured.

Link Source: https://arknights.fandom.com/wiki/Contingency_Contract

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