This game was really fun!
From a design standpoint, the one-card hand limit reduces the number of options available to the player, thereby making all the strategy go into the deck-building and less into the play of the hand. This has the potential to be really interesting! However, this game hasn't shown me that potential yet. You've crafted a solid card game - which is already impressive given the time constraints - but what I'm not getting is, once you've subtracted the multiple cards in your hand, what is gained? Some additional simplicity? That's not bad, depending on what you're going for. But if there's something else you wanted to show me with this game, I didn't receive it.
Also, I feel like the lack of being able to reshuffle your discard pile makes Focus almost useless, because skipping past a card is rarely worth it. Focus could be a really interesting mechanic, but again, I don't feel its potential was realized in this jam.
Regardless, I enjoyed the heck out of playing it - thanks for making it!