It has been quite a while since I was looking for music similar to Igorrr. Igorrr makes completely mad breakcore with elements of any type of music imaginable, including metal. Pryapisme does something similar, but here the metal seems to be the basis and the breakcore elements ‘additions’.
Pryapisme is also completely insane. They go from extremely fast metal to jazz, orchestrations and classical music. They are even weirder than Carnival In Coal. There seem to be more of these weird metal outfits, but none are as strange (and good!) as Pryapisme. Their latest album is not their best in my opinion, but here is an album to try if you want something weird and different.