Gloom-shroom

The Gloom-shroom shoots Fumes in all directions, but with short range, heavily damaging all zombies nearby. It is purchased from Crazy Dave for $7500 and is an upgrade for the Fume-shroom. It is unlocked after level 4-4. It is useful in Last Stand.

Suburban Almanac Entry
Gloom-shroom

Gloom-shrooms release heavy fumes in an area around themselves.

Must be planted on fume-shrooms

"I've always enjoyed releasing heavy fumes," says Gloom-shroom. "I know a lot of people aren't cool with that. They say it's rude or that it smells bad. All I can say is, would you rather have your brains eaten by zombies?"

Cost: 150

Recharge: very slow

Overview
The Gloom-shroom causes normal damage with each shot, and while its range is the surrounding patches in all eight directions, the attacking speed is very fast. Note that they can hit zombies that are eating Wall-nut on any of the squares in its range, but not Tall-nuts (unless a Pole Vaulting Zombie, Pogo Zombie, or Dolphin Rider Zombie jumps into it). With a proper strategy, you could beat the level extremely easily. This plant is essential to surviving any large number of flags in Survival: Endless. It is also a key ingredient in the completion of Wall-nut attack.

The Gloom-shroom does four DPS (damage per second) to any given target in its range, so it does as much damage as a Gatling Pea. Its fumes can also hit every single target in its range, like the Fume-shroom, even if they have shields. However, again, it does not have as much range.

Strategy
One tactic for Pool and Survival: Endless levels is to build a 2x3 area of Gloom-shrooms in the right-hand side of the pool, all covered by Pumpkins. These will handle pool zombies as well as those in rows 2 and 5. This strategy has the side effect of leaving zombies in rows 1 and 6 mostly unscathed, so although these can generally be handled with Cob Cannon shells or consumable plants, such as the Jalapeno, a better idea is to put Gloom-shrooms in the fifth and sixth columns in rows 2 and 5, plus using Fume-shrooms in rows 1 and 6 in the fourth and fifth columns. Optionally, Garlics can be placed in rows 1 and 6 to funnel zombies into the Gloom-shroom's line of fire (although this obviously won't work against Gargantuars and Zombonis, while a Spikeweed/Spikerock can be placed in rows 2 and 4/5.

Another effective use is a row of Gloom-shrooms in rows 2 and 4/5, with two Garlics at the very end. All land zombies will be moved to rows 1 and 6 and be annihilated. Snorkel Zombies and Dolphin Rider Zombies will make it necessary to add a two colums of Pumpkins on Lily Pads in the pool to allow time for the Gloom-shrooms to destroy them. This strategy is perfect for the Mini-game Last Stand, since it can handle all of the zombies encountered. Their effectiveness is hampered by their short range, which makes them vulnerable to Gargantuars when planted on land which will cause them to be smashed.

They can also be used in Survival: Endless (in the column second furthest to the left, on land) in order to dispose of Digger Zombies (and Imps), as there is generally not enough room for Split Pea.

Trivia

 * While the Fume-Shroom has fire range of four spots, but can only do one hit per zombie, per hit. As for Gloom-Shroom, it has a fire range of one square(one spot in eight directions), but can do four hits per zombie, per fire, which means the Gloom-Shroom was intended for the middle row(or the pool), while the Fume-Shroom was possibly intended for every row, just from a far distance.
 * GloomShroom.png Gloom-shroom is the only plant that looks up as opposed to the left, right, or at the screen (not including the Cob Cannon while firing).
 * These work amazingly with Garlics, Spikerocks and Spikeweeds.
 * The Gloom-shroom is the only mushroom upgrade since the Gold Magnet isn't considered a mushroom because it is diurnal.
 * Living up to its name, the Gloom-shroom has a constant sad expression.
 * Despite the Gloom-shroom having a constant sad expression, its seed packet in the Suburban Almanac in the PC and DS version shows a picture of it like it's smiling.
 * The Gloom-shroom is one of the two plants having its eyes on its mushroom cap, the other one being the Doom-shroom.
 * It is ironic that the Gloom-shroom holds its breath while shooting out fumes, because in its Suburban Almanac entry, it says it doesn't mind the smell.
 * The Gloom-shroom, the Doom-shroom, the Fume-shroom, and the Ice-shroom are the only mushrooms that frown.
 * The Gloom-shroom, the Starfruit, the Cattail, the Cob Cannon, and the Threepeater are the only plants that can fire outside the lane it is planted on.
 * The Gloom-shroom and the Doom-shroom are the only mushrooms that don't have a design on its mushroom cap.
 * The Gloom-shroom has the shortest range of fire, only one square around itself (not including instant kills such as the Chomper).
 * For some reason, the Gloom-shroom knows when to fire its fumes even though its eyes are facing upward.
 * There is a glitch on the DS version where the Gloom-shroom will puff non-stop on zombies even though the puffing animation shows only four puffs at a time.
 * The Gloom-shroom will still only deal 4 puffs worth of damage, even though it puffs continuously.
 * Gloom-shroom's name was spelled in its Suburban Almanac entry without the dash between "Gloom" and "Shroom."
 * The Gloom-shroom is the strongest AOE projectile plant.
 * The Gloom-shroom is very useful in Survival: Endless and Last Stand.
 * The Gloom-shroom is ranked #2 for firing in the most directions (8), the 1st being the Cattail (all lanes), the 3rd being the Starfruit (5).
 * The Gloom-shroom is the only mushroom upgrade that degrades its range than the non-upgraded version.
 * Gloom-shroom's fumes can still pass through groups of zombies and shields.
 * There is also achievement in this wiki known as Octuple Circuit, with Gloom-shroom shooting image.