Even without stacking a ton of spells, being able to tutor one dragon straight onto the battlefield is powerful but when you storm off, you could end up putting three, four, or even five dragons into play all at once
Its sacrifice ability costs two mana, which significantly limits how much you can use it if you also want to cast spells in the same turn
With a haste enabler, like Lightning Greaves, and a way to untap creatures or generate mana on death, like Pitiless Plunderer, you can create an infinite loop of Joo Dees, filling your graveyard with the Surveil trigger
I find them super comfy to shuffle and play with
If you cast Quasiduplicate or the Replicate side of Repudiate // Replicate, you can respond with Dualcaster Mage, copy the copy spell copying your Dualcaster Mage, and then repeat