I think the requirement of Ayyubid transition "controling demascus" is not historically accurate
because the Fatimid dynasty fell in 1169 and never tack back demascus
I think the requirement of transition should be changed or be automatic at 1170


source en.wikipedia.org/wiki/Fatimid_Caliphate
"After the decay of the Fatimid political system in the 1160s, the Zengid ruler Nūr ad-Dīn had his general, Shirkuh, seized Egypt from the vizier Shawar in 1169. Shirkuh died two months after taking power, and the rule went to his nephew, Saladin.[23] This began the Ayyubid Sultanate of Egypt and Syria."