As u/FalloutBoy5000 notes, its not outside the realm of possibility to have at least some of the power 9 in an Arena power cube. While the Power Nine would help power up the MTG Arena cube, they may be too powerful
We'll all understand perfectly if you do
There is a BR aggro Pirate deck and a UB control deck that is all about controlling the board until you can drop some big Sphinxes from Amonkhet
Giving all your dragons indestructible means you can swing and block without fear, and the bonus of stacking +1/+1 counters every upkeep quickly snowballs, all on top of a potential alternate win condition
Based on the early data, however, $10-15,000 is looking like a reasonable prediction
It ETBs with energy, sure, but it can convert energy to creatures without tapping, which, of course, means you can generate infinite tokens pretty easily with the other cards here