The core mechanic is great and sliding tiles around felt responsive and satisfying. I enjoyed babysitting my lil fella and trying to corral off all the enemies - there were times were it felt like one of those sliding puzzles which was really neat. I would love to see special tile types, like tiles with walls that only allow movement on particular sides or something like that - would be interesting to see what ideas you can come up with to expand on this design!
Presentation was great too, good job!