User blog comment:Hawkeye2701/Kubo Lost Count/@comment-24165551-20141109171330

It's also possible he's one of the four special characters used in the German language: A (umlaut), O (umlaut), U (umlaut), or b (eszett, a ligature that looks like the beta symbol). This would of course mean there are three more Ritters out there. Seems unlikely for the same reason that a symbol like ! or ? is unlikely.

Perhaps one of the Sternritters that were introduced in the second invasion took his place. Again, this would mean that there may be more Ritters who replaced the ones that died in the first invasion (the Lloyds, the three Ritters Zaraki killed, and Driscoll Berci). This is assumes that Yhwach can make new Sternritter once a given epithet-holder dies. The epithets might get "used up" with each Sternritter, although it seems more likely that Yhwach can create as many as he wants.