This makes prowess best used in decks with few creatures but multiple cheap spells that also replace themselves by drawing additional cards
I played a ton of it in Standard on MTG Arena, and when Alchemy rolled out tweaks to the dungeon cards making them stronger, I wracked up a ton of wins
The connected commons and uncommons have gone away, and part of making the booster playable included balancing colors, so the new Play Boosters will do that
Referencing the card "Millstone," Mill decks seek to put cards from the top of an opponents' library directly into their graveyards, whilst also often drawing players additional cards
If you pay enough energy, you effectively get to hold on to the cards that were in your hand
As a player with a limited budget, you're almost certainly better of picking up something like a Commander 2020 deck for $40 than spending $40 on a handful of cards from a Secret Lair drop