Sounds like it may be a non-native species to drains, and not just normal gray-water waste (globs of hair and soap, etc). A snake should take care of normal gray-water clogs. Shampoo cap? Pieces of a loofa (sp?) sponge? Something like that? Root-Rooters extended razor sharp blade attachment may do the trick, but if it's a significant sized foreign object, get ready to start taking the pipes apart (and splice in mor PVC if that's the case).

I think kharzhak pooped in the tub, but won't admit it.

Perhaps a cherry bomb? That does the trick..