This is a common misconception, so if you're just joking I'll prepare myself to be wooshed in the hopes it helps someone else reading this. There is a concept of many universes which permits slightly differing laws of physics (actually different fundamental constants), but many worlds isn't that one. Many Worlds just says that quantum wavefunctions don't collapse. It doesn't posit any "universe" that the Copenhagen interpretation doesn't allow, it just lets them exist side by side.
You sound like you'd be interested in Max Tegmark's "Our Mathematical Universe". There are probably multiple levels of multiverses, and in our local "stack" we have 4, where the Many Worlds mechanism is sitting on level 3. Some don't have this level 3, but may have fewer or more levels, using mechanisms foreign to this multiverse, depending on their laws of physics.
