You may cast any number of spells from among those nonland cards without paying their mana costs
Whichever way you play it, this is cheap enough and powerful enough to be good in any deck
The more people that open these sealed boxes, the more rare the cards get, and prices will only increase as we move forward
(To proliferate, choose any number of permanents and/or players, then give each another counter of each kind already there.) The value of X is determined only once, as Tromell's last ability resolves
I remember watching The Professor rock him in Game Knights, and I can't help but think of him fondly
The ability to choose what modes to select when casting the card makes them highly valuable (both in-game and oftentimes monetarily), as you can tailor their decisions based on your own board state