I don't think anyone has ever had a positive record with a mono Eeveelutions deck
Shadow of the Enemy can break a game wide open
Their model is best described as pay to not play as a lot of grind can be skipped by opening ones wallet, but as both games have fun mechanics (Duel Links even has another entire game and format within called Rush Duel), if you love them, you wont mind grinding them
Suppress the urge to craft four of a single card
The trick here is that the copy is NOT a token, but rather a new game piece (spawned by conjure, a digital-only mechanic that's unique to MTGA), and therefore itll trigger Mythweaver Poqs ability again and again until MTG Arena crashes or you casually win the game with the likes of Impact Tremors
I prefer Fiery, as you won't have to tap a creature to get the same cost, but this CAN be played cheaper if you have multiple creates