Holidaying in Iberia

Start OUTSIDE the Iberian Struggle, wade in, and see it ended (any of the three main endings counts). The wiki's route: the 1178 Mu'minid ruler - invasion CB on Castille, then give away your non-Iberian domain, move your capital into the conquered land, drop the head-of-faith title so you can convert to Muwalladism, and ride it to the Status Quo ending. Or the greedy route: Eudes of Anjou in 867, stacking this with Kings to the Seventh Generation - as King of France nobody stops you conquering into Iberia, converting to Mozarabism and ending the struggle at your leisure. The wiki's own phrase: three achievements in one run, at minimum.