Board Thread:Bloons Wiki and BTD News/@comment-5056929-20130809071543/@comment-7150475-20130825151228

Towers
These are only Tier 1 upgrades, wait 'til you see the Tier 2 upgrades ;) Switching towers subtracts 3 from your maximum energy, although if it is your first time, you only lose 1 maximum energy.

Boomerang Thower: Quite a powerful tower, with an irregular popping pattern. Pops up to three bloons per turn. Usage: Aim at bloon adjacent to Boomerang. Boomerang loops in a perpendicular direction and hits up to 2 more bloons.
 * Red Hot 'Rangs (0-1): Can pop Lead Bloons

Isn't Red Hot Rangs the teir 2 upgrade for the boomerang monkey?