NieR: Automata's 3C3C1D119440927 DLC unlocks three challenging Colosseums. After receiving the Mysterious Letter, you'll need to locate these arenas to unlock unique rewards. Here's a guide to their locations:
Quick Links
Trial of the Sand Colosseum Location
This Colosseum is situated in the desert. From the "Desert: Center" access point, look to the right (facing the desert entrance) for an orange diamond-shaped marker. A machine guards the entrance, but it poses no threat. Completing this Colosseum unlocks the Destroyer Outfit (A2) at Rank S.
Gambler's Colosseum Location
Begin at the "Flooded City: Coast" access point. Follow the path towards the coast, the same route used to protect the resource ship. At the end, locate a waterfall to the right. Circle around the building to the left of the waterfall to find a Resistance member guarding the entrance. A 1,000G bribe unlocks access to the Gambler's Colosseum. Reaching Rank S rewards you with the Revealing Outfit (2B).
Underground Colosseum Location
9S ONLY: This Colosseum is accessible only when playing as 9S.
Start at the "Forest Zone: Center" access point. Follow the left edge of the forest until you find machines training near a large waterfall. Pass through the waterfall to enter the Underground Colosseum. The Rank S reward is the Young Man's Outfit (9S).
