Very promising game!
Some critique:
* Merging and applying items on units should have a confirmation box with a preview, I have accidentally merged or applied items I dodn't want to simply by forgetting that it was selected. In the case with the merger it was the wrong one that was kept with the bad stats
* The game is quite challenging in the beginning, but once you overcome the first 10-15 rounds the enemies stops getting more difficult. They should instead scale and the units you buy should also scale (and become more expensive), I was on round 170 when I decided to just abondon the run. Ofcourse the money reward should scale as well.
* add a log so you can analyze what happened during the previous fight
* Allow us to fast forward messages.
Great mechanic and good overall :)