Nier: Automata [official site] is so wonderful and complete in itself that I might be happy to skip DLC and not even play again for a fair while. I'll return later, absolutely, but for now I might pass on the DLC released today. 3C3C1D119440927 is its name, and adding arena battles and costumes is its game. Given that this is Nier: Automata, I suspect it may be more complicated than that. I mean, beyond the fact that it has battles against the CEOs of Square Enix and PlatinumGames; that's not even a secret. Here, have a gander at the DLC's launch trailer:
Oh hell, what am I saying? I absolutely do want to fight those fights. I might feel bad bashing those bots but they seem up for it.
3C3C1D119440927 adds three coliseums across the world (you may have previously found their entrances?) with arena battles, offering prizes like several costumes of characters from the first Nier and bits like coloured hair sprays. Also in are new songs and, Squeenix say, "Masks with unique 'on equip' effects." I wonder what those do. Please don't tell me; let me find out for myself.
The 3C3C1D119440927 DLC is £9.49/13,99€/$13.99 on Steam.
I had hoped that the DLC might be accompanied by a patch fixing some of Nier: Automata's technical problems but no, apparently not. Once again, try this player-made tool to fix some of the issues. The Nier team have said they were investigating reports of problems but nothing useful has come of that yet.