over the course of making my game Greedy Tower Defense, I have made lots of changes to @warfame 's original design, changes that i am sure would be useful to other game devs.
Immense credit to @warfame , as this engine is a modification of his design for a tower defense game. Changes I have added a pulse tower, whom slows down enemies. I have added a SELL FUNCTION, whitch can be activated by pressing t. I have added a plantation who generates five cash every second there is an enemy onscreen. I have added the variable "ismechanized", whitch is only set to one for vehicles and changes the death costume (so your vehicles dont blood splatter) as well as dealing less damage to vehicles, yet more damage to infantry. I have added a cooldown mechanic, so every tower has to cool down in a changable number of shots, as well as waiting a changeable amount of time for the cooldown. I have added an "end" sprite instead of edge sensing so if the enemies have big costumes they will not die immediately. I have added clone detection for the enemy, so clones will not try to spawn clones if you implement an extra wave broadcast or something of the sort. I believe that this is all of the major changes that i have made, but if not you can scold me in the comments ;) As always, everything is free to use if you give credit and comment here a link to the project that uses this.