Thanks for the feedback! The artists did make a death effect, I just didn't have time to put it in. They made quite a few fx that didn't get time to be put in. Explaining the mechanics was also something that just didn't have time. I usually do shorter jams, 12 hours - 2 days, this was the 1st 2 week jam I did, and thought I could tackle more than I was able to. I pulled 2 all nighters at the end just to get it even playable with the mechanics we intended. Such is the nature of overscoping.

One thing I think wasn't explained well enough at all was the resource system. We call those "Threads" you start with 4 of them. While they are gold, they are available for the player to use. Each card has a Thread Cost in the top left that says how many Threads they'll use. When a Thread is spent, it turns gray until the next wave, where it becomes available again. Some cards have 2 numbers in the top left, the 2nd number being how many turns a Thread is used for. When such a card is played, the Threads it used turn blue, and designate how many waves left they have in such a state. Blue Threads are busy working and can not be used to play cards until they are gold again. There are 2 different types of Thread Reservation, one performs the action every turn (a buff card for instance will provide it's buff for every turn the thread is blue), others perform their action when the Thread completes its job, turning gold again (Overclock is an example of this). Some card animations and icons would go a long way in explaining a lot of this.

I think there are some balancing issues early game, you can get RNG'd out of being able to do much (your example of long range tower not attacking is one of these, as is only having 1 web tower in your opening hand, as a web tower requires another web tower to create a web.) Unfortunately I didn't have enough time to play test this to even notice that until post-jam, and would be something I fix if I put more work into the project. As for the long range towers, their radius really needed to be a ring, not a circle, every little thing takes time.

I think the lack of displaying the deck, discard, and trash piles also creates some confusion. Your starting deck is 5 cards large, and it's pseudo-randomized at the start of the run. When you defeat a level and add a new card, it adds it to your deck as an option to play. When you draw your cards each wave you draw from the deck, not the complete list of cards. Meaning if you get unlucky with card picks and have very few tower cards in your deck, the game can get very hard. I would make the cards you have a choice from a bit smarter if I work on it more, favoring to usually put a tower card there, maybe tapering off to equal chance in the later game as you start to need less of them.

Its unfortunate, but I don't think anyone will even see the boss we worked on. We built the game completely level-less to test specific things really easy and fast, so it wasn't in until the last few hours, they really needed to be done earlier.

As for your question about timers, it keeps the game moving, it forces the player to make a choice and play. Tower defense games can really drag on, especially in longer waves and later levels. I'd remove it for this game completely going forward because I feel like it clashes with the card game aspect of this game because it ends up removing your cards while you're in the middle of trying to play them.