Cool! I don't see that many tower defense jam submissions. This take feels nice to play and I liked how you could move the towers after you'd bought them. The hexagonal grid was cute. Would be nice if the towers changed appearance when you upgraded them levels. The UI for adding elements to towers I didn't think was that intuitive, took me a minute to work out how to equip them. Some more variety of enemies that synergise with the elemental effects would be great. I felt you acquire crystals too fast/easily for it to be very challenging, but can't expect a jam submission to be really fine tuned difficulty wise. Nice job