Regrow

Regrow is a bloon property that lets a damaged bloon grow back its lost layers. Every 3 seconds, a Regrow bloon that is not fully popped regenerates one layer, up to the layer it started as. A half-popped Regrow Rainbow that slips past your main defense can be back to a full Rainbow by the time it reaches the exit. Regrow bloons are easy to spot because they are heart-shaped.

Every regular bloon up to Ceramic can have the Regrow property. Regrow does not change a bloon's RBE, but it can force you to deal far more damage than the RBE suggests if your towers are too slow.

How Regrow works

• A Regrow bloon regenerates one layer every 3 seconds while it is still alive.
• It can only regrow up to its original layer. A Regrow Yellow never grows into a Pink.
• Regrown layers give no cash when you pop them again, and they do not add to your towers' damage counters.
• If a Regrow bloon splits into several children, each child can regrow on its own. This is how Regrow groups multiply: pop a Regrow Zebra into a White and a Black, let both regrow into Zebras, and you now have two Zebras instead of one.
• DDTs release Camo Regrow Ceramics, but those Ceramics cannot regrow back into a DDT.
• A Fortified Regrow bloon that regrows to its starting layer does not get its Fortified armor back.

When do Regrow bloons appear?

• Round 17: 12 Regrow Yellows, the first Regrow round.
• Rounds 19, 25 and 29: more Regrow Yellows mixed into larger groups.
• Round 31: the first Regrow Zebras. From here on, Regrows with multiple children can multiply if left alive.
• Round 36: Camo Regrow Greens.
• Rounds 39 and 42: Regrow Rainbows.
• Round 59: Regrow Ceramics.
• Round 61: 150 Regrow Zebras.
• Round 62 and later: Camo Regrow Rainbows and Fortified Camo Regrow Ceramics.

In Alternate Bloons Rounds, Regrows first appear on round 3. Some challenges also change the Regrow rate or make every bloon Regrow.

How to deal with Regrow bloons

Just pop them fast

The most efficient answer is simply enough damage, attack speed and pierce to finish Regrow bloons before they get a chance to grow back. Three seconds is a long time if your defense is solid. Most dedicated anti-Regrow upgrades are not worth their price compared to more popping power.

Block Regrow

• Grow Blocker (0-1-0 Monkey Village): a cheap upgrade that stops Regrow bloons from regenerating while they are inside the Village's radius. Place the Village where your defense actually fights.
• Ezili's Heartstopper (level 3 ability): blocks Regrow on every bloon for 10 seconds and lets towers pop Purple Bloons.
• Freezing: frozen bloons cannot regrow.

Remove Regrow

• Druid Heart of Oak (0-2-0): attacks turn Regrow bloons into normal bloons.
• Engineer Monkey Cleansing Foam (0-3-0): removes Regrow and Camo and pops Lead.
• Ice Monkey Ice Shards (3-0-0): removes Regrow and Camo when damaging bloons.
• Ezili: at higher levels, her curse strips Regrow, Camo and Fortified from non-MOAB bloons.
• Corvus: his Haunt effect removes Regrow.

Extra damage to Regrow

The Beast Handler's Gyrfalcon deals increased damage to Regrow bloons.

Regrow on bosses

The boss Lych has a Regrow trait that heals it for a percentage of its maximum health every few seconds, healing more as it loses skulls. Regrow blockers and removers work on Lych too, but Lych can restore the trait when it absorbs tower buffs. See the Boss Events page for more.

Common mistakes

• Leaving a lone tower at the end of the track. A weak backup tower that chips a few layers off Regrow Rainbows does almost nothing, because they regrow before the next hit.
• Spreading damage too thin. Many low-damage towers spread along the track are worse against Regrows than one strong cluster that pops everything in a few seconds.
• Ignoring round 31. The first multi-child Regrows can snowball on a weak defense.
• Overpaying for de-Regrow. Unless a challenge is built around Regrow, extra damage is usually the better buy.

Regrow farming

Because regrown layers give no cash, you cannot farm money by letting Regrow bloons regenerate and popping them again. Regrown layers do still count toward a tower's pop count, which matters for a few pop-based requirements, but they will never make you richer.

Frequently asked questions

How fast do Regrow bloons regenerate in BTD6?

One layer every 3 seconds, up to their original layer. Challenges can change this with a Regrow rate modifier.

What round do Regrow bloons start?

Round 17 in standard games, with 12 Regrow Yellows. In Alternate Bloons Rounds they appear on round 3.

What stops Regrow bloons?

Grow Blocker (0-1-0 Village) blocks regeneration in its radius, Ezili's Heartstopper blocks it for 10 seconds, and freezing stops it. Heart of Oak, Cleansing Foam and Ice Shards remove the property for good.

Do Regrow bloons give more money?

No. Regrown layers do not give any cash when popped again.

Can Ceramic bloons be Regrow?

Yes. Regrow Ceramics appear from round 59, and DDTs release Camo Regrow Ceramics when destroyed.

Can MOAB-class bloons be Regrow?

No regular blimp has the Regrow property, but the boss Lych has a Regrow-style healing trait.