Endless Upgrade Monkey

The Endless Upgrade Monkey is a very special monkey with 4 paths. His base tower has the same stats as a Dart Monkey but his attack speed is 3.8% faster. He appears as a casual monkey wearing a shirt with a disco-style infinity symbol on it. But here's the special part; all paths are endless. The upgrades never end. (This will always be a stub.)

Upgrades
All costs are at medium difficulty and all percentages and comparisons are compared to a 0-0-0-0 EUM.

Path 1

 * Sharp Shots ($120) - Darts can pierce an extra Bloon.
 * Razor Darts ($200) - Darts can pierce three Bloons total.
 * Spiked Darts ($450) - Darts can pierce five Bloons.

Path 2

 * Quick Shots ($100) - Darts are thrown 10% faster than usual.
 * Very Quick Shots ($200) - Darts are thrown 25% faster!
 * Triple Shot ($500) - Throws three darts at a time.

Path 3

 * Enhanced Range ($80) - Darts can be thrown 7.5% farther.
 * Biosight ($150) - Darts can be thrown 15% farther and can pop Camo Bloons.
 * Crossbow ($750) - Wields a powerful crossbow with arrows that pop 3 layers off of each Bloon hit.

Path 4

 * Faster Darts ($75) - Darts move around 3% faster.
 * Speedy Darts ($200) - Darts travel 10% faster!
 * Splodey Darts ($650) - All darts explode upon impact.