The new EA Mythic format was successfully decoded ;) I uploaded all muls (including index files). Usage: just download required archive, unpack it to uo classic directory and enjoy ;) You can use UO Fiddler or Inside UO (with some restrictions to tiles above 0x3FFF range) and viewing client's arts, gumps, sounds and maps.
http://126.96.36.199/ruosi/188.8.131.52/Art.zip - art.mul and artidx.mul ~40MB
http://184.108.40.206/ruosi/220.127.116.11/Gumps.zip gumpart.mul and gumpidx.mul ~18MB
You're wrong: old convert will not work correctly with 18.104.22.168+, EA Mythic mixed the chunks inside uops, chunks are no longer stored in sequence (0,1,2...), it can be as 0, 8, 100, 1, 30, 21 etc. That's why runuo/sphere dirty hack for maps (reading by offset, skipping headers -> it's not EA Mythic intended way) will not work anymore and server will crash while attempting to read data from mapXlegacymul.uop All i can say: index data is stored with mul data in the same file There is a hint inside client.exe. Good luck!
Format? You already got it That's usual UOP files, nothing new. I'm not planning to release 'guide'. I will upload files but you can, of course, not use it if it's problem for you and, of course, you can ask for help all runuo, sphere and pol communities to get EA 'mini-secret' how to understand those files' contents Good luck.