With quite an original concept and beautiful elaboration, this game has to be the best one I've yet played in this jam. I'm generally not a big fan of TD games, but this was a fun experience from start to finish.
The controls were smooth and responsive, difficulty set in about right level, style is charming and the upgrade system makes the game more fun and removes the tedium. I also like the fact that, although it doesn't make that much sense, your character is actually faster when carrying the tower, which leads to a dillema, if I should pick up the tower to be able to faster get those sweet sweet upgrade crystals. It also sets itself nicely for possible future updates with more maps and bigger enemy variety.
Overall, really good job and I really enjoyed playing it.
P.s.: manual pause button would be great, as I was playing the game during my breakfast, which made things really hectic. ;)