Do you not understand how a multiverse works? It's the same as the old heroes of folk oral tradition--we take the same characters, we make different stories, we have free rein to beat them up as much as we want, but when we return them to the shelf (sometimes dead, sometimes exiled, sometimes turned into gods or trapped in hell for eternity, whatever) it's with the understanding that the next authors can take them back off and do whatever new thing they want with it.