Oil Rig

The oil rig generates 3 money per second but stops if the games has no bloons on screen

path 1
faster oil: generates oil at 0.7 seconds: costs $1000

even faster oil: generates oil at 0.5 seconds: costs $2000

leaky oil: oil starts sprinkling making bloons slip stunning them for 3 seconds: costs $10000

flaming oil: makes 10x more oil and bloons that slip on the oil get caught on fire doing 3 layers of damage per second: costs $25000

make your own path 2