The Xyz x Link Festival has begun, and with it, missions for the event have been added:
-Duel in Festival 20 times (200 gems)
-Normal or Special Summon a monster in Festival 30 times (200 gems)
-Win a Duel in Festival 10 times (200 gems)

For a total of 600 gems.
Note that these missions are labeled as “November Festivals”, so it’s likely that they stack with the Extra Zero Festival as well.