Erosion

Erosion

Difficulty	Advanced
Music	Sunshine Serenade
Default Co-op division	Free-for-all
Introduced	Version 37.0
Entrances	6	Exits	6
Junctions	0	Water?	Yes

Path lengths (RBS)
Path		Easy	Medium	Hard
First		9.0	8.2	7.2
Second		11.2	10.2	9.0
Third		14.6	13.3	11.7
Fourth		13.6	12.4	10.9
Fifth		9.8	8.9	7.8
Sixth		5.4	4.9	4.3

Erosion is an Advanced map in Bloons TD 6, introduced in version 37.0. It takes place at an ice floe which gradually melts as rounds progress. A polar bear is present on the map, which moves to stay on solid ice every time a piece melts. The polar bear does not interact with towers or Bloons.

This map's concept was designed by /u/TheWiseTroll, for the "200k Map Contest Competition" held on /r/btd6, and it was selected as a winner along with Dark Dungeons and Covered Garden.

Layout

Erosion has 6 different paths, with only one of which being active at a time. On round 1, this starts with the path in the bottom-left.

At the end of round 17 and every 18 rounds after (35, 53, 71, 89), the land between the current track and the next tracks will collapse, selling all land towers on the ice and changing the path to the next lane. Pat Fusty, Ice Monkeys, Mermonkeys, Sun Temples, and True Sun Gods are not sold and transform into water towers when the land under them erodes. Additionally, any towers in range of an Arctic Wind or above's ice platforms will also not be sold. The map reaches the top-right lane and stops eroding on round 90, and the round 90+ lane is the shortest lane out of any lane in any map that gives rewards in BTD6 (only Blons has a shorter lane). Heli Pilots cannot be placed on the top-right section of this map, despite having enough space to do so (can be observed by placing a Banana Farm, which has a larger footprint and can be placed).

Boss Bloons always appear on the third path, regardless of the round number.

Strategy

Erosion is not particularly difficult outside of CHIMPS mode, as towers sold by the eroding mechanic give back cash, though care must still be taken to avoid placing heroes on eroding land. This is not the case in CHIMPS. The eroding mechanic, along with the extremely short length of the round 90+ track, make Erosion generally considered as an Expert-level, mis-categorized map that is only bested by X Factor in terms of the difficulty of Advanced maps. Attempt to place as few towers as possible outside of the top-right in CHIMPS, as they will be sold for no money before the hardest rounds come. For the early game and mid-game, use global towers placed on the top-right or towers able to be teleported. Alternatively, Arctic Wind and its ice platforms can be used, now that itself is allowed to be placed on water.

Recommended towers and upgrades

Name	Portrait	Reasoning
Corvus		His Spirit can pop Bloons from anywhere, and his Spear spell is very powerful throughout the early game. At level 7, he can use Spirit Walk to move to a new lane away from collapsing ice and constantly gain mana. During the mid-game, his Spellbook can save up titanic amounts of money for a solid tower that defeats the late-game, such as Carpet of Spikes and Bloon Exclusion Zone. In the late-game, Corvus still has solid utility with Ancestral Might and Overload.
Carpet of Spikes		It is powerful on this map due to the extremely short length of the round 90+ lane. The short length of that lane allows for extreme concentration of spikes that deal massive damage with every passive & active ability, easily sweeping DDT rounds, doing solid damage to ZOMG shells, and eliminating Round 100's BAD as a problem altogether. Use the 0-5-2 crosspath, as without it, most spikes will be wasted on inactive lanes, and use a MIB or Embrittlement to give it DDT popping power.
Advanced Intel		This upgrade allows Monkey Subs to adapt to lane changes by attacking within the range of other towers. It is primarily used for the early game, with Airburst Darts coupled with this upgrade contributing significantly throughout.
Arctic Wind		Arctic Wind platforms are important if wanting to salvage land towers, especially for Round 90 and above, which offers little space, and opens room for larger towers including Heli Pilot (which artificially cannot be placed on the top-right island). Additionally, Arctic Wind offers Ceramic slowdown for a decently low cost.

Gallery

This article or section needs more screenshots. See the screenshot guidelines for more information on what screenshots are needed and how to add them. The editor that added this notice elaborates: r18, r36, r54, r72, r90

• 
  Concept art
• 
  Easter theme
• 
  Fireworks theme
• 
  Halloween theme
• 
  Holiday theme
• 
  Island statue

In other languages

This section was last updated for: version 48.1

Language	Text	Notes
Arabic	المحو	—
Danish	Erosion	—
German	Erosion	—
Spanish	Erosión	—
Spanish (Latin America)	Erosión	—
Finnish	Eroosio	—
French	Érosion	—
Italian	Erosione	—
Japanese	腐食	—
Korean	침식	—
Dutch	Erosie	—
Norwegian	Erosjon	—
Polish	Erozja	—
Portuguese (Brazil)	Erosão	—
Russian	Эрозия	—
Swedish	Erosion	—
Thai	Erosion	—
Turkish	Erozyon	—
Chinese (simplified)	侵蚀	—
Chinese (traditional)	侵蝕	—

References

• Path lengths sourced from the BTD6 Index

Navigation

v • t • e Maps in Bloons TD 6
Beginner Monkey Meadow • In The Loop • Skull Tweak • Three Mines 'Round • Spa Pits • Tinkerton • Tree Stump • Town Center • Middle of the Road • One Two Tree • Scrapyard • The Cabin • Resort • Skates • Lotus Island • Candy Falls • Winter Park • Carved • Park Path • Alpine Run • Frozen Over • Cubism • Four Circles • Hedge • End Of The Road • Logs Intermediate Lost Crevasse • Luminous Cove • Ancient Portal • Sulfur Springs • Water Park • Polyphemus • Covered Garden • Quarry • Quiet Street • Bloonarius Prime • Balance • Encrypted • Bazaar • Adora's Temple • Spring Spring • KartsNDarts • Moon Landing • Haunted • Downstream • Firing Range • Cracked • Streambed • Chutes • Rake • Spice Islands • Protect The Yacht* Advanced Mushroom Grotto • Party Parade • Sunset Gulch • Enchanted Glade • Last Resort • Castle Revenge • Dark Path • Erosion • Midnight Mansion • Sunken Columns • X Factor • Mesa • Geared • Spillway • Cargo • Pat's Pond • Peninsula • High Finance • Another Brick • Off The Coast • Cornfield • Underground Expert Tricky Tracks • Glacial Trail • Dark Dungeons • Sanctuary • Ravine • Flooded Valley • Infernal • Bloody Puddles • Workshop • Quad • Dark Castle • Muddy Puddles • #Ouch • Blons*
* Not playable in standard solo or Co-op play