Chocobos will also be represented in at least one way, with the 0/1 creature Sazh's Chocobo, which powers up every time the player gains a land
Whenever your opponent casts their first non-creature spell each turn, you may draw a card, unless your opponent pays X (where X is Esper Sentinel's power)
I like a spread of Birds of Paradise, Noble Hierarch, and Ignoble Hierarch for my mid-powered Cubes and would caution against going much heavier than that
Gifting an opponent the monarchy is annoying, but in a deck with card draw punishers like Nekusar, the Mindrazer, you can work around it
That is what appears to have happened with one of the Magics first intellectual property crossovers
If it's countered, it will go to your graveyard