i have those ideas: every tower have 4 paths 8 upgrades per path (or 12) 1st path:basic upgrading system. 2nd path:intermediate upgrading system (more expensive). 3rd path:advanced upgrading system (even more expensive). and 4th path:EXTREME UPGRADING SYSTEM AND EPIC (EVEN EVEN EVEN EVEN MORE EXPENSIVE)

play bloons tower defence 6 here

Community content is available under CC-BY-SA unless otherwise noted.