The Eleventh Abyss is ruled by Queen Hecuba, who is a daughter of the Chaos Mother that survived the end of the 4th Cycle.
There is a segment of the Abyss Initiation that allows the Initiates to travel through time. This infintely risky and dubious practice invariably results in Chaos and Insanity, but nevertheless is widely practiced in the Eleventh Abyss. It is as a result of this, that there is also now a second Queen Hecuba, usually referred to as Dark Hecuba, who is apparetly a time paradox duplicate of the original Hecuba.
The Eleventh Abyss was a favourite holiday destination of an individual called Landor Yorke. In fact, he married Hecuba, and they both travelled widely through time. At some point, Landor and Hecuba became at odds, and Landor changed his alliance to Dark Hecuba, and Hecuba returned to the 11th Abyss, defeated the Draken and revealed that she was now married to Lord High President Rassilon of Gallifrey. All indications are (like if you just look at him it is blindingly obvious) that Rassilon is actually Landor’s son.