I really liked the mechanics of expanding the sides and being able to move the towers. Very interesting as tower defense! I was able to win it without combining the towers, simply because I forgot hahaha
Viewing post in CELLVASION jam comments
If you are going to balance it, it would be good to promote the use of the mechanics within the gameplay:
Maybe when you pick up a tower it can take the direction of the nearest one and the tower it points to creates a sprite of the enhanced tower above it with low opacity. A beam of electricity pointing towards the tower to be joined can also work!
Success with your game! I will be attentive if you update it