Really cute game with quite some potential :D
I liked the idea of special effects, they give a bit more depth to the classical tic-tac-toe. On the player's side however they're a bit too random or so it felt. From the description it does seem that you're heading in a cool direction with it, so it will be interesting to see where this goes.
For the future, maybe a quick intro could also be added? Just to spice up the story some more ~
Also, probably not intended to work this way but I dragged a block into the enemy and accidentally pushed him in the floor oops ^-^'