I've never played Blackjack before (although I already knew about the 21 rule), so it took me a couple of tries to figure out what "HIT" and "STAND" meant (i.e. cards can't be given to players that declared "STAND"). Figuring out that the cards in the modifier deck do what their number values represent also took a while, since I didn't know that face cards have a value of 10. Once all that was all figured out however, the game became really enjoyable since I was always betting (or hoping) that players wouldn't receive any "bad cards" from the unmodified deck or declare "STAND" before I could give them better modifier cards.
Making it so that you (the dealer) could see everyone else's cards but couldn't see what one of your own cards was (like in classic blackjack) was the real genius move since it meant you were basically playing against yourself, or in this case the house (making the whole "double agent" narrative even more genius). Actually "winning" the game is surprisingly hard since you basically have to make at least two players win in a single game in order to bankrupt the house in one swoop, otherwise the chips raked in from two players will be enough to keep the night going.
The game as a whole is visually clean and mechanically polished, especially for a first-time submission. It almost reminds me of Balatro, and you could probably make it into a full game by expanding the mechanics and gameplay even further.
The only real problem is that the music audio is scuffed, but I'm not sure if it's just a problem on my end or not.