Cool, nice to see another tower defense card game!
I liked the overall gameloop... building up the defenses, chasing down the staff when stolen, and drawing/using cards. I also really liked that you could attack yourself!
The overall graphic look is pretty good, and the music fits. More SFX might add to the experience!
It was pretty confusing on my first run, I didn't really understand what to do and kept fighting myself as my cards weren't refreshing. However, that may have been a bug... I did run into quite a few bugs. On my second run, I was able to build up a bunch of defenses, but after the 1st wave my "Draw" timer locked and I couldn't really get new cards (i could use some of the old ones though, even ones that said they were locked). Lucky for me, the defense setup I had made was good enough to carry me to the end.
The balance is probably a bit off, as you mentioned yourself in the comments, but balancing TD is hard... believe me, I know first hand!
I enjoyed my time playing this game! I think with a little bug fixing, polish, and maybe a little expansion (more mechanics, a story, additional unit types) this game will really shine! Awesome work!