Here's the challenge: make sure that there is a significant war between Byzantium and at least one of the Christian Spanish states.
The only conditions are that the war should not be primairily fought in Byzantium's core territories (e.g. no 4th Crusade scenarios et al) and that no POD earlier than 1000 AD should be used.
Bonus points for scenarios that include a unified Spain, and/or a Seljuk conquest of Anatolia, and/or at least one battle on the Iberian Peninsula or the Balearics that involves Byzantine forces.