Cold Front

Cold Front is a fourth-row Magic knowledge that makes the lightning bolts that fork off Ball Lightning's orbs freeze the bloons they hit. You need 4 Knowledge Points in the Magic tree, Warm Oak and a one-time 250 Monkey Money. It unlocks Vine Rupture.

The knowledge has been reworked twice. Before version 30 it added a 25% freeze chance; from version 30 it made the orbs always freeze. In version 39, Ball Lightning itself got a guaranteed freeze from its orb without any knowledge, and Cold Front was changed to its current effect: the extra forked bolts freeze too.

How it changes the game

Ball Lightning (4-x-x Druid) launches slow-moving orbs of lightning that shoot bolts at nearby bloons as they travel. The orb already freezes what it touches. With Cold Front:

• Much wider freezing: every forked bolt also freezes its target, so a single orb can lock down bloons across a large area instead of only those it passes through.
• Stalling power: combined with the Druid of the Storm's tornado blowback, the top-path Druid becomes a strong crowd-control tower. This is particularly helpful against dense Ceramic waves and Super Ceramics in freeplay.
• Damage trade-off: frozen bloons can only be popped by attacks that hit Frozen Bloons. Hot Magic, which is a prerequisite of this branch, makes all your Magic towers able to hit them, but some Primary or Military towers nearby may lose targets until the ice breaks.

It only affects Ball Lightning and higher top-path Druids. Damage, pierce and attack speed are unchanged.

Is it worth it?

Priority: situational. For players who use Ball Lightning as a stall, it is a strong upgrade. If you never build top-path Druids, its main value is the route: Vine Rupture gives Spirit of the Forest a big damage and stun ability, and leads (with Deadly Tranquility) to Tiny Tornadoes.

Compared with Arcane Impale, the other common fourth-row pick (route to Mana Shield), Cold Front usually comes second.

Where it works

Cold Front works wherever Monkey Knowledge is enabled, including Magic Monkeys Only, Impoppable and freeplay. It is disabled in CHIMPS and in challenges that switch knowledge off.

Frequently asked questions

What does Cold Front do?

The lightning bolts that fork off Ball Lightning's orbs freeze the bloons they hit.

Doesn't Ball Lightning already freeze bloons?

Yes, since version 39 the orb itself freezes. Cold Front adds freezing to the forked bolts.

Can freezing hurt my defense?

Sometimes. Towers that cannot hit Frozen Bloons lose targets while bloons are frozen. Magic towers with Hot Magic are fine.

How much does Cold Front cost?

One Knowledge Point and a one-time 250 Monkey Money, with 4 Magic points and Warm Oak.

What does Cold Front unlock?

Vine Rupture.