Cold Snap

"Can freeze and pop Lead and Camo Bloons."

- In-game description

 (formerly known as Metal Freeze) is the second upgrade of Path 1 for the Ice Monkey in BTD6. It allows Leads and Camos to become frozen and popped by the Ice Monkey, plus gives the Ice Monkey with camo detection. This upgrade inherits the effects of Permafrost.

It costs $295 on Easy, $350 on Medium, $380 on Hard, and $420 on Impoppable.

Summary
Cold Snap comes with both early lead-popping power and early camo-popping power. While the lead-popping isn't as reliable as alternate options, it does come with the Permafrost effect for further slowing down bloons. In addition, the camo detection allows for direct camo-popping of Ice Monkeys.

As for higher-tier upgrades, this upgrade is generally reserved for Icicle Impale to damage DDTs in the absence any external buffs, mainly Monkey Intelligence Bureau or Acidic Mixture Dip spam.

Tips

 * It is not very reliable at popping Lead Bloons, but it is never a bad option for countering Lead Bloons, as its Permafrost effects can come in handy for certain occasions, especially versus incoming Ceramics.
 * Cold Snap is generally used with Icicle Impale sometimes when direct DDT-popping power is required.
 * Adding this with Cryo Cannon allows a 2-0-3 Cryo Cannon to deal Round 63 quite effectively by popping the Leads and slowing the Ceramics.
 * Because of the Version 25.0 reworks, Cold Snap is required for Snowstorm ability to freeze Leads and DDTs, unless given Acidic Mixture Dip or has Monkey Intelligence Bureau in radius. Likewise occurs for Icicle Impale.

Trivia

 * Prior to Version 28.0 which reworked Metal Freeze/Cold Snap into a camo-detecting tower, 2-0-0 Ice Monkey in BTD6 is basically equal to a 2-1 Ice Tower in BTD5 except without Enhanced Freeze (equivalent to Enhanced Freeze and Larger Radius in BTD6).
 * Cold Snap could be a reference to the pre-BTD6 upgrade Snap Freeze, which is fitting because the Cold Snap's upgrade icon depicts a snapped bloon inflicted by cold.