NieR: Automata's 3C3C1D119440927 DLC unlocks three challenging Colosseums. After receiving the Mysterious Letter, use these guides to locate them:

Quick Links

• Trial of the Sand Colosseum
• Gambler's Colosseum
• Underground Colosseum

The DLC introduces optional content and cosmetic rewards. Each Colosseum features six ranks with progressively difficult enemies.

Trial of the Sand Colosseum

Located in the desert. From the "Desert: Center" access point, look right (facing the desert entrance) for an orange diamond-shaped structure. A machine guards the entrance, but poses no significant threat. Completing Rank S rewards the Destroyer Outfit (A2).

Gambler's Colosseum

Accessible from the "Flooded City: Coast" access point. Follow the path to the coast (similar to the resource ship mission). At the end, locate a waterfall. Circle around the building to the left, finding a Resistance member guarding the entrance. A 1000G bribe unlocks access. Rank S completion yields the Revealing Outfit (2B).

Underground Colosseum

9S ONLY. Start at the "Forest Zone: Center" access point. Follow the left edge of the forest to a group of training machines near a large waterfall. Pass through the waterfall to access the Colosseum. The Rank S reward is the Young Man's Outfit (9S).