Haha! I don’t know about 10 rippers, but let's see if we can come up wih a decent 30 wound army that would play nice with the others.
Sure, but if Archaon is 20 wounds, you can field at most 11 models. You just need a good round of fire with sallies, or a trio of ripperdactyls from the clouds, and it's game over.
Well for the Archaon/Nagash player, not necessarily the partner. But watch out if you get paired with Nagash /Archaon guy because your partner has a big target on their head that could take you both out.