Sequels Naming Starter Pack
Starts off normally, with just a number: Sequel 2
Soon removes the number, but adds a sub title.
Sequels: Another Sequel
Numbers are sometimes used
As letters. Sequ3ls
Fifth and tenth installments sometimes use Roman numerals
Sequels V, Sequels X
Eventually one will just be the same name as the original. It is done either inexplicably or as a reboot.