So I got back into Yu-Gi-Oh cards and I have to say the game mechanics have come a very long way. With the introduction of XYZ, Synchro, and Pendulum monsters strategy is more important than ever (so much for my legacy decks), in any case XYZ monsters are the best and should be put in any deck regardless of whether its a ritual deck to a Ghostricks deck. I have a few decks my favorite of which is my Dark Paladin deck which centers around Dark Magician and Buster Blader, XYZ monsters go great with this deck. As you can see from the picture there are several combos that you can break out if you're in a pinch or are in the winning stretch.