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Monkey Sub icon

BTD6 tower guide

Monkey Sub BTD6 Upgrade Paths and Paragon

Monkey Sub is a BTD6 Military tower for water-map coverage, Advanced Intel range, decamo support, missile burst, and Nautic Siege Core planning.

Updated 2026-06-13 by TDGameTools.

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Monkey Sub route map

Monkey Sub starts simple, then splits into three Tier 5 jobs

Use Monkey Sub when water placement gives it wide reach or when decamo support makes your land towers more reliable. It depends heavily on map water and vision, so it is not equally valuable on every map.

BaseWater coverage and camo support
5-0-0Energizer
0-5-0Pre-Emptive Strike
0-0-5Sub Commander
ParagonNautic Siege Core

Quick answer: what is Monkey Sub for?

Monkey Sub is strongest on water maps where Advanced Intel or Submerge and Support can cover large parts of the track. Top path supports and decamos, middle path fires missiles and First Strike burst, and bottom path buffs a Sub-focused damage plan.

Visual route map

Base Monkey Sub splits into three recognizable routes

Read the route by role first, then decide which path solves the current run.

Base Monkey Sub iconBaseMonkey Sub
Energizer route marker5-0-0Energizer
Pre-Emptive Strike route marker0-5-0Pre-Emptive Strike
Sub Commander route marker0-0-5Sub Commander
Nautic Siege Core iconParagonNautic Siege Core

How Monkey Sub usually fits into a run

Use Monkey Sub when water placement gives it wide reach or when decamo support makes your land towers more reliable. It depends heavily on map water and vision, so it is not equally valuable on every map.

CategoryMilitary monkeys
Core jobWater coverage and camo support
Main cautionIt depends heavily on map water and line-of-sight rules.
ParagonNautic Siege Core

Upgrade routes

Monkey Sub's three path identities

Use this as a role summary, not a patch-perfect damage table.

Submerge and Support upgrade visual3-x-xSubmerge and Support
Bloontonium Reactor upgrade visual4-x-xBloontonium Reactor
Energizer upgrade visual5-x-xEnergizer
5-0-0

Top path

Energizer

Decamo, support, and cooldown utility from water.

Best when
Camo stripping or ability cooldown support helps the whole setup.
Watch out
Submerged support may stop behaving like normal direct damage.
Beginner read
Use it to make other towers see camo before bloons reach them.
Ballistic Missile upgrade visualx-3-xBallistic Missile
First Strike Capability upgrade visualx-4-xFirst Strike Capability
Pre-Emptive Strike upgrade visualx-5-xPre-Emptive Strike
0-5-0

Middle path

Pre-Emptive Strike

Missile damage and timed burst against MOAB-class threats.

Best when
Blimps need to be softened before they cross the map.
Watch out
Missile burst is expensive if the rest of the defense cannot clean up children.
Beginner read
Plan for what comes out of the blimp after the burst.
Triple Guns upgrade visualx-x-3Triple Guns
Armor Piercing Darts upgrade visualx-x-4Armor Piercing Darts
Sub Commander upgrade visualx-x-5Sub Commander
0-0-5

Bottom path

Sub Commander

Sub army scaling and steady dart pressure.

Best when
You are using several Subs with enough water and map coverage.
Watch out
One isolated Sub Commander is not the same as a full Sub setup.
Beginner read
This path rewards committing to the tower family.

Common uses

When Monkey Sub makes sense

  • Strip camo before bloons enter a land-based damage cluster.
  • Use Advanced Intel-style coverage to attack through other tower vision.
  • Add First Strike or Pre-Emptive Strike when blimps need early burst.
  • Prepare the Monkey Sub family for Nautic Siege Core Paragon planning.

Mistakes

What usually goes wrong

  • Forgetting that the map needs useful water for the tower to shine.
  • Buying Sub Commander without enough other Subs to justify the plan.
  • Bursting MOABs without cleanup for the bloons released afterward.
  • Using decamo support too late in the track for the main towers to benefit.
Nautic Siege Core icon

Paragon branch

Nautic Siege Core

The Monkey Sub Paragon combines the three Tier 5 Monkey Sub paths. Use the TDGameTools calculator and planner pages before committing cash, pops, upgrade tiers, extra Tier 5s, and Geraldo totems.

Energizer route marker5-0-0
Pre-Emptive Strike route marker0-5-0
Sub Commander route marker0-0-5
to
Nautic Siege Core iconNautic Siege Core
Base towerMonkey Sub
Medium price$400,000
Releasedv41.0
CalculatorParagon Degree CalculatorEstimate degree from cash, pops, tiers, extra Tier 5s, and totems.PlannerParagon Degree PlannerPlan target degrees before committing an expensive upgrade.ExplainerHow Paragon Degree WorksUnderstand power buckets before chasing a target degree.Degree 100Geraldo Totems for Degree 100Estimate how many totems close the final gap.

Related BTD6 pages

Beginner guideBest BTD6 Towers for BeginnersChoose towers by the problem you need to solve.ToolBloon Counter CheckerCheck whether your setup is missing camo, lead, purple, or DDT coverage.ReferenceAll BTD6 TowersCompare every non-hero tower by category, beginner role, and caveat.

Sources and scope

This page is a concise TDGameTools tower guide, not an official wiki clone. Use it to understand roles and internal planning links, then verify live game values for exact patch or boss-event planning.

Ninja Kiwi BTD6 page Monkey Sub Nautic Siege Core

FAQ

What is Monkey Sub good for in BTD6?

Monkey Sub is strongest on water maps where Advanced Intel or Submerge and Support can cover large parts of the track. Top path supports and decamos, middle path fires missiles and First Strike burst, and bottom path buffs a Sub-focused damage plan.

Which Monkey Sub upgrade paths should I compare?

Monkey Sub has three main route identities: 5-0-0 Energizer, 0-5-0 Pre-Emptive Strike, 0-0-5 Sub Commander. Compare them by the job you need, not by a single permanent best path.

Does Monkey Sub have a Paragon?

Yes. Monkey Sub connects to Nautic Siege Core, so use the calculator and planner links before committing a late-game or boss setup.