You benefit more with card draw abilities of The Great Henge, Elder Gargaroth, and Tribute to the World Tree to get as many creature cards as you can into your hand
If you "double" a creature's power more than once in a turn, each doubling effect applies independently
You'll want to set up turns where Esper Terra generates ten mana with the last chapter, transforms back to Terra, Magical AdeptTerra, Magical Adept, and has haste from one of the several haste enchantments to immediately use six of that mana to transform back to Esper Terra for more copy shenanigans
If it's a creature card, you may turn it face up
Its average price is about $200,000 - $300,000 .
Then, he can use his ability Cheer, which allows you to draw and card and add a counter to another creature when a creature with a counter attacks