Hellfire Depths

Hellfire Depths is the 8th world in Plant vs Zombies 2: It's About Time (GMXX version). It is the final world before the Time Twister, and has a total of 29 levels, 9 plants, and 2 upgrades. It can be unlocked with the Hellfire key (Obtained by completing Frostbite Caves Day 8). It takes place in the year 666, and upon arriving there, Crazy Dave and Penny fall through a hole into the depths of hell. The world is kind of like a reverse Frostbite Caves, the main gimmick being Fire Plumes that can't be planted on and heat up nearby plants. Plants that are heated up too much will be burned out of existence, so ice plants are recommended to keep that from happening. It is also dark in this world, meaning sun doesn't fall from the sky, and mushrooms can be used without the Coffee Bean. The lawnmowers in this world are skeleton hands.

In-game Description
''Delve into the depths of hell in the year 666! It's hot down there, so keep your plants cool to beat the heat!''

Hazards
Fire plumes can't be planted on, but if they erupt they will severely heat up all plants in a 3x3 area around them. Sometimes rocks will fall from the sky and damage plants they land on.
 * Fire Plumes
 * Falling Rocks

Surprise Attack
The surprise attack of this world is called "Hellfire!". When it happens, all Fire Plumes erupt and 5 Literal Imps are blasted to the 4th column.

Chilling Plants
Chilling plants are used to keep plants from overheating, and are immune to heating. The Chilling Plants are:
 * IceBerg Lettuce
 * Snow Pea
 * Winter Melon
 * Hurrikale
 * Freeze Mushroom
 * Ice-shroom
 * Lichen
 * Chilly Pepper

Plants
This world has 9 plants that can be obtained, 4 of which return from the original Plants vs Zombies.
 * Ice-shroom (obtained after Day 1)
 * Pult-shroom (obtained after Day 3)
 * Lichen (obtained after day 7)
 * Umbrella Leaf (obtained after day 10)
 * Chilly Pepper (obtained after Day 12)
 * Dart-shroom (obtained after Day 14)
 * Rose (obtained after completing all BOMB! All Together levels.
 * Gloom-Shroom (obtained after completing all Locked and Loaded levels.
 * Doom-shroom (obtained after Day X)

Zombies
This world has a total of 11 Zombies, and one boss. All zombies in this world are resistant to fire. Toughness: normal
 * Demonic Zombie

Speed: basic Toughness: protected
 * Demonic Conehead

Speed: basic Toughness: hardened
 * Demonic Buckethead

Speed: normal Toughness: normal
 * Demonic Flag Zombie

Speed: basic Toughness: normal
 * Literal Imp

Speed: hungry

Flies above most plants, can breathe fire one space in front of it to heat up plants. Toughness: great
 * Scapegoat Gargantuar

Speed: hungry

Crushes plants with upside-down cross, throws Literal Imp when damaged enough. Has more health than a regular gargantuar (can withstand 3 instant kills), but is weaker (Must smash a plant twice to crush it) Toughness: solid
 * Flaming Zombie

Speed: basic

Can light itself on fire to heat plants in a 3x3 area around it.

Toughness: protected
 * Zombiegon

Speed: creeper

Can breathe fire 3 space in front of it to severely heat up plants. Toughness: solid
 * Plume Raiser Zombie

Speed: basic

Creates Fire Plumes. Toughness: protected
 * Warlock Zombie

Speed: creeper

Can change the order of your plant rows. Toughness: protected
 * Rock Thrower Zombie

Speed: slow

Throws rocks at your plants to damage them. Toughness: hardened
 * Zombie Hellhound

Speed: hungry

It's howl raises the attack power of zombies that surround it. Toughness: undying
 * Boss: Zombot Demonic Devil

Rains rocks down on plants, blasts a columns fiery air to heat up plants, shoots fireballs that instantly burn plants and scorch tiles, heals nearby zombies.

See: Hellfire Depths - Day 16

Upgrades
A ninth seed slot. It is unlocked when the player kills a total of 500 zombies in this world. A tenth seed slot. It is unlocked when the player kills a total of 1,000 zombies in this world.
 * Extra Seed Slot 4
 * Extra Seed Slot 5

Levels
Hellfire Depths has 16 main levels, 4 Key Gates, 1 Bonus level, and 1 endless zone. -Level Type: Normal
 * Day 1

-Plants: Choice

-Zombies: Demonic Zombie, Demonic Conehead, Demonic Flag Zombie, Flaming Zombie.

-Reward: Ice-shroom -Level Type: Normal
 * Day 2

-Plants: choice

-Zombies: Demonic Zombie, Demonic Conehead, Demonic Buckethead, Demonic Flag Zombie, Flaming Zombie.

-Reward: Coin Bag -Level Type: Special Delivery
 * Day 3

-Plants: Puff-shroom, Pult-shroom, Snow Pea, Ice-shroom, Infi-nut.

-Zombies: Demonic Zombie, Demonic Conehead, Demonic Flag Zombie, Flaming Zombie, Literal Imp.

-Reward: Pult-shroom
 * Day 4

-Level Type: Normal

-Plants: Choice

-Zombies: Demonic Zombie, Demonic Conehead, Demonic Buckethead, Demonic Flag Zombie, Literal Imp.

-Reward: Coin Bag -Level Type: River Qycks
 * Day 5

-Plants: Pea Pod.

-Zombies: Demonic Zombie, Demonic Conehead, Demonic Buckethead.

-Reward: Coin Bag -Level Type: Normal
 * Day 6

-Plants: Choice

-Zombies: Demonic Zombie, Demonic Conehead, Demonic Buckethead, Demonic Flag Zombie, Flaming Zombie, Literal Imp, Zombiegon.

-Reward: Coin Bag -Level Type: Special Delivery
 * Day 7

-Plants: Fume-shroom, Lichen, Chard Guard.

-Zombies: Demonic Zombie, Demonic Conehead, Demonic Buckethead, Demonic Flag Zombie, Flaming Zombie, Literal Imp, Zombiegon.

-Reward: Lichen -Level Type: Gargantuar Battle
 * Day 8

-Plants: Ice-shroom, Puff-shroom, Pult-shroom, Lichen, Wall-nut.

-Zombies: Demonic Zombie, Demonic Conehead, Demonic Buckethead, Demonic Flag Zombie, Flaming Zombie, Literal Imp, Scapegoat Gargantuar, Zombiegon.

-Reward: Final Key (Unlocks Time Twister) -Level Type: BOMB! All Together
 * Day 9

-Plants: Cherry Bomb, Jalapeño, Ice-shroom, Potato mine.

-Zombies: Demonic Zombie, Demonic Conehead, Demonic Buckethead, Demonic Flag Zombie, Flaming Zombie, Literal Imp, Zombiegon, Plume Raiser Zombie.

-Reward: Coin Bag -Level Type: Normal
 * Day 10

-Plants: Choice

-Zombies: Demonic Zombie, Demonic Conehead, Demonic Buckethead, Demonic Flag Zombie, Literal Imp, Zombiegon, Plume Raiser Zombie.

-Reward: Umbrella Leaf -Level Type: Locked and Loaded
 * Day 11

-Plants: Sun-shroom, Pult-shroom, Pumpkin, Umbrella Leaf, Sun Bean, Lichen, Ice-shroom.

-Zombies: Literal Imp, Rock Thrower Zombie.

-Reward: Coin Bag -Level Type: Normal
 * Day 12

-Plants: Choice

-Zombies: Demonic Zombie, Demonic Conehead, Demonic Buckethead, Demonic Flag Zombie, Flaming Zombie, Zombiegon, Plume Raiser Zombie, Rock Thrower Zombie, Warlock Zombie.

-Reward: Chilly Pepper -Level Type: Normal
 * Day 13

-Plants: Choice

-Zombies: Demonic Zombie, Demonic Conehead, Demonic Buckethead, Demonic Flag Zombie, Literal Imp, Scapegoat Gargantuar, Flaming Zombie, Zombiegon, Warlock Zombie, Zombie Hellhound.

-Reward: Coin Bag -Level Type: Normal
 * Day 14

-Plants: Sun-shroom, Dart-shroom, Choice.

-Zombies: Demonic Zombie, Demonic Conehead, Demonic Buckethead, Demonic Flag Zombie, Flaming Zombie, Zombiegon, Plume Raiser Zombie, Rock Thrower Zombie, Warlock Zombie, Zombie Hellhound.

-Reward: Dart-shroom -Level Type: Normal
 * Day 15

-Plants: Choice

-Zombies: Demonic Zombie, Demonic Conehead, Demonic Buckethead, Demonic Flag Zombie, Literal Imp, Scapegoat Gargantuar, Flaming Zombie, Zombiegon, Plume Raiser Zombie, Rock Thrower Zombie, Warlock Zombie, Zombie Hellhound.

-Reward: Note from Zomboss

-Level Type: Boss Battle
 * Day 16

-Plants: Ice-shroom, Pult-shroom, Freeze Mushroom, Umbrella Leaf, Dart-shroom, Gloom-shroom, Wallnut.

-Zombies: Zombot Demonic Devil, Demonic Zombie, Demonic Conehead, Demonic Buckethead, Demonic Flag Zombie, Literal Imp, Scapegoat Gargantuar, Flaming Zombie, Zombiegon, Rock Thrower Zombie, Zombie Hellhound.

-Rewards: Hellfire Depths Vasebreaker Level Pack, Endless Zone and Day X unlocked. -Level Type: Special Delivery
 * Day X

-Plants: Fume-shroom, Lichen, Rose, Gloom-shroom, Chilly Pepper, Dart-shroom, Doom-shroom.

-Zombies: Demonic Zombie, Demonic Conehead, Demonic Buckethead, Demonic Flag Zombie, Literal Imp, Scapegoat Gargantuar, Flaming Zombie, Zombiegon, Plume Raiser Zombie, Rock Thrower Zombie, Warlock Zombie, Zombie Hellhound.

-Reward: Doom-shroom

Brain Busters
This world has 2 exclusive brain busters, and 4 Key Gates.
 * Special Delivery
 * Locked and Loaded
 * Save our Seeds
 * River Qycks
 * BOMB! All Together

Heck-tic Stages of Grief
Heck-tic Stages of Grief is the endless zone of Hellfire Depths. The player starts out with the Sun-shroom, Puff-shroom, Lichen, Ice-shroom, and Wall-nut.

Trivia

 * This is the first World in the game to be based off of something religious.
 * It is one of 2 Worlds in Plant vs Zombies 2: It's About Time (GMXX version) that cannot be unlocked with a world key, the other being Time Twister.
 * The Fire Plumes were originally called "Fire Geysers"
 * The Lichen and Rose are the only completely new plants introduced in this world, since Pult-shroom and Dart-shroom were originally planned for Dark Ages.
 * The main music for this world resembles the Hell theme from Worms.