Monkey Knowledge
Cheap ‘Rangs
Cheap 'Rangs in BTD6: Boomerang Monkey costs $50 less on every difficulty ($315 to $265 on Medium). Worth it, and what it unlocks.
Base cost of Boomerang Thrower reduced by 50.
Guide
Cheap 'Rangs is a second-row Primary knowledge that lowers the placement price of every Boomerang Monkey by a flat $50. On Medium, a Boomerang Monkey drops from $315 to $265. It requires Increased Lifespan, costs one Knowledge Point and no Monkey Money, and unlocks Extra Bounce.
The discount is applied after the difficulty price multiplier, so it is the full $50 on every difficulty: $270 to $220 on Easy, $340 to $290 on Hard and $380 to $330 on Impoppable. Version 57 fixed an older issue where flat discounts like this one were calculated incorrectly outside Medium.
How it changes the game
The saving applies every time you place a Boomerang Monkey, not just once per game:
- Opening rounds: a Boomerang Monkey on round 1 or 2 arrives sooner, which matters on maps where it is your first damage tower.
- Spam strategies: in Races or Primary Only games where you place several Glaive Ricochets or Bionic Boomerangs, $50 per tower adds up quickly.
- Late game: on a $40,000+ tower the discount is irrelevant.
It only reduces the base tower price. Upgrades cost the same as without the knowledge. When you sell a Boomerang Monkey, the sell value is based on what you actually paid.
Is it worth it?
Priority: good. As a standalone effect, $50 is small. Two things make this node better than it looks:
- It is the only route to Extra Bounce, Recurring 'Rangs, Hard Press, Long Turbo, Bionic Augmentation and Mega Mauler. That branch is one of the strongest in the Primary tree.
- In Races, every early dollar counts, and Boomerang starts are common.
Compared with Fraggy Frags, its sibling under Increased Lifespan, Cheap 'Rangs is the better first pick for most players because of what sits below it.
In Primary Only games, where Boomerang Monkeys are often the main early damage, the saving arrives on the very first round and keeps paying off as you add more throwers.
Where it works
Cheap 'Rangs is active in any mode that allows Monkey Knowledge, on all difficulties. It is disabled in CHIMPS, so CHIMPS prices are always the normal ones. Challenges can also disable knowledge, which changes the price you see in the shop. If a strategy depends on exact cash on a specific round, check whether knowledge is on.
Frequently asked questions
How much does a Boomerang Monkey cost with Cheap 'Rangs?
$265 on Medium, $220 on Easy, $290 on Hard and $330 on Impoppable.
Does Cheap 'Rangs reduce upgrade prices?
No. Only the base price of the Boomerang Monkey is lowered.
Is the discount the same on every difficulty?
Yes. It is a flat $50 applied after the difficulty multiplier.
Is Cheap 'Rangs worth buying?
Yes, mostly because it leads to Extra Bounce, Long Turbo and Bionic Augmentation.

