the concept is originally from the game (name forgotten) i once played, which was indeed pretty unique XD
The help page infers how to control, and the ui infers what you have and how much a builfing will cost. But there isn't anything that infers how to Complete a level. Please forgive my carelessness :(
Besides, because of the algorithm that checks connection, it will take more computing time when the connection is long, making it nearly impossible to complete the 3rd level. I'll try to fix it when I have time. Anyway, thanks for playing~ Wish you have a good time!