Shimmer

"Gains a dark magic attack that periodically reveals location of all nearby Camo bloons permanently."

- In-game description

 is the third upgrade of Path 3 in Bloons TD 6 for the Wizard Monkey. It produces a series of large blasts every 2.5s around its radius that reveal Camo Bloons and DDT's permanently. Each blast of Shimmer reveals up to 200 Camo Bloons at once, but like Cleansing Foam the shimmer pierce can be consumed by non-camo bloons too. Although slow, the shimmer effect has a very generous detection range and blast radius.

The Wizard also receives a large range bonus, from 40 to 60. The shimmer spell's radius (both for detection and usage) is larger than the tower's radius, at 70.

It costs $1,445 on Easy, $1,700 on Medium, $1,835 on Hard, $2,040 on Impoppable.

Summary
Compared to other options of camo support, while Shimmer is fairly reliable when placed on curves, it is more expensive than Submerge and Support but also more restrictive than Radar Scanner. Usually, Shimmer is only used when there is a lack of water for Submerge and Support and space for Radar Scanner village, such as decamoing the top path on Infernal.

Tips

 * The best placement of Shimmer is to place it around a corner or curve somewhat near the start of the track.
 * Shimmer can also be used to remove camo from Camo Leads without popping them themselves unless Path 2 upgrades are bought. Interestingly, this can be used together with a Lead to Gold Alchemist so that it maximizes income generation.
 * Note that Shimmer has a delay on the shimmer attack, which is notable when decamoing Camo Pinks. To alleviate this issue it is best to still have some towers that can cleanup some camo, for example by getting the Wall of Fire crosspath, or low tier Ninja Monkey or Spike Factory.
 * An Archmage will automatically gain Shimmer.
 * 1-0-3 Shimmer can activate over walls, despite not doing so in earlier versions. Upgrading along Path 2 for the Wall of Fire upgrade provides an additional powerful attack but does not improve Shimmer.
 * If you don't really care about the Shimmer blasts, just use this as a stepping stone to Necromancer: Unpopped Army.

Trivia

 * Before the Version 3.0 update, this upgrade did not have a full stop at the end of its description in BTD6, being the only instance of this occurrence.
 * Previously the shimmer attack did not see over walls, even with the Guided Magic crosspath.
 * This was fixed as of presumably Version 25.0, which had a massive damage types rework for many upgrades in the game, although discovered in 27.3.