(+ SO ALL CAN SEE) When you purchase the Path-Right Tier-Four upgrade of a tower, it will receive a special ability. Find it by looking at the southwest part of the screen. The ability will show you what it does when you hover over it and has a cooldown after using. The ability could be: Money, full-screen coverage of a tower's shots, summoning a special tower or buffing towers in range for a short period of time, or more.
@Jim
0rava is not going to update this anymore. His/her hands are full with Mutilate-a-Doll: Enhanced Edition. Put ideas on their profile to might have it in MAD:EE!
East, don't you get it? Monsters are unlocked and upgraded using putty, so it makes sense that Putty flung on it enrages it. Twig Snappers, Goo factories, Pebble Shiners, and even Putty squishers themselves don't use putty, so it doesn't make sense. And tell me this: How do you fling putty on your own stuff? Catapults have too high power to do such short shots.
I think that Slimeattikus is an overpowered prize for Creature Carnage. Would you give a L29 a combo of a Fang, a Bandito, and a Project X that fission's upon death to Low-levels? That would be overpowered!
 "Bloons TD 5"){kind=icon}
 "Reactance"){kind=icon}
 "Backyard Monsters (removed)"){kind=icon}
 "Mutilate-a-doll"){kind=icon}
 "Reactance 2"){kind=icon}
 "The Nokkians 2"){kind=icon}
 "Boss Slayer"){kind=icon}