I spent a lot of time and came up with constructive discussion of what may have gone wrong with Oko, Thief of Crowns in design
Using Enchantments that return to your hand anytime they go to the graveyard is a nice strategy too, as you can get back the Enchantments effect while also making sure you continue to have fuel for Ertais ability
1 Nightpack Ambusher
2 Secret Lair Drop Market Price: $32.13 Blue does not host many Dinosaurs, as this Elder Dinosaur originally from Rivals of Ixalan is one of only six in Magics history, but what a Dino it is
By the same token, though, its a waste to run more than one copy of it, and it loses out on the very thing that tends to define XYZ Monsters: their unique Extra Deck utility
Without it, you could be out both the card and the payment if something goes wrong, so always weigh the small upfront cost against the potential loss