[[WMG: Crazy Dave is crazy because.....]]
* He's craaaaaaaaaaaazy!

[[WMG: Crazy Dave is responsible for the [[ZombieApocalypse zombie apocalypse]].]]
He used to work in hazardous materials disposal, but was driven insane from excessive exposure. He then took some radioactive waste and tossed it into the graveyard. Why?
* He was bored.
* He didn't have anybody to sell his seeds to.
* He's craaaaaaaaaaaaazy!

[[WMG: Crazy Dave is secretly {{Running Both Sides}}.]]
Actually, he's a [[TheChessmaster chessmaster]] who
* caused the zombie apocalypse
* sells plants to defeat the apocalypse,
* creates this game (and makes money off of it)
* causes you to be too busy playing the game to notice his other schemes
* and gets away with it by pretending to be (or actually being) craaaaaaaaaaaaazy!

[[WMG:What each plant represents]]
* Peashooter: [[StandardFPSGuns Pistol]]
* Sunflower: Electric generator
* Cherry Bomb: [[CaptainObvious Bombs]]
* Wall Nut: DeployableCover
* Potato Mine: [[CaptainObvious Landmine]]
* Snow Pea... Ice gun?
* Chomper: Meat grinder
* Repeater: Assault rifle
* Threepeater: Shotgun
* Gatling Pea: [[CaptainObvious Gatling Gun]]
* Spikeweed/Spikerocks: {{Caltrops}}/[[PopTheTires Spike Strip]]
* Lobbed-shot plants: Mortar
* Cob Cannon, Banana Launcher, Missile Toe: SCUD/ICBM
* Coconut Cannon: [[CaptainObvious Cannon]]
* Jack O'Lantern: [[FireBreathingWeapon Flamethrower]]
* Dusk Lobber: Cluster Bomb launcher

[[WMG:Crazy Dave is [[VideoGame/TeamFortress2 Team Fortress 2]]'s Pyro]]
They're both crazy and have a similar body structure.
* From the grunts, they sound male.

[[WMG: Crazy Dave is from a video game universe.]]
How else can he fit all that stuff in his van and STILL have room for the numerous plants and himself?
* His car could be a portal to {{Hammer Space}}.
** This explains the {{Konami Code}} being mentioned.

[[WMG: Crazy Dave is Dave Seville]]
He was driven insane by the chipmunks.
** So that's why he loved hunting Squirbos...

[[WMG: The entire game is one introverted gardener's dream about an upcoming family gathering]]
The plants are the gardener's job seeping into the dream. The zombies represent family members, including a hockey fan relative and a nephew who plays football, the hordes of zombies attacking is the gardener's fear and dislike of crowds seeping into the dream. The gathering is possibly a funeral, or otherwise at a cemetery, which seeps into the dream as the gravestones at night that mysteriously appear out of nowhere, while not existing in the day. (Or perhaps the gardener works at a cemetery.) The minigames represent different versions of the dream that occur throughout the night.
* "Those sunflowers aren't for eating! No, leave those peas alone, they're not ripe yet! Watch where you're go- [[BerserkButton STOP STEPPING ON MY SPROUTS]]!"
** It could also be the nightmare of a gardener for hire who also regularly works at a creepy graveyard.

[[WMG: [[Franchise/{{Batman}} Poison Ivy]] is somehow involved it all this.]]
Well, she could be the one making the plants. Or she could be the hero of the story.
* There was an episode of ''WesternAnimation/BatmanTheAnimatedSeries'' where Poison Ivy was supposedly trying to start a new life with a family. It turned out to be a ruse, but at the end we see part of her really did love being a house wife. Perhaps she's taking a sincere crack at it.

[[WMG: The game is a twisted, digital form of [[Manga/DeathNote Death Note]].]]
The original release contains an obvious Music/{{Michael Jackson}} reference. He died shortly afterwards, and Pop Cap changed it to a disco zombie. What would happen if they added another zombie referencing someone?
* In PvZ2, they recently added Gold Bloom, who's named after Jeff Goldblum. I'd buy life insurance if I were him...

[[WMG: The Chomper is Audrey II.]]
Leading to an InferredHolocaust where your blood, rather than your brains, is consumed.
* The game states that Chomper ''auditioned'' to play Audrey II (or at least a stunt double), but didn't get the part.

[[WMG:Crazy Dave has already had his brains partially eaten by the zombies,]]
He wasn't crazy when all of this started. He was [[CrazyPrepared ready when it began]], with his seeds on hand to defend his house. When his defenses were breached, the zombies started eating his brain, but he managed to escape before they got too far. He abandoned his house and stockpiled all his remaining seeds and other supplies in his car. He was left with only part of his brain, leaving him unable to speak normally or think quite right. The pot on his head hides his exposed brain and protects it from further attacks.
* Possibly {{Jossed}}. Sometimes, his saucepan helmet will somehow jump and spin over his head, but we never do see the backside of his skull.
** If his brain was eaten, even partially, he'd be unable to do all the motions he does in the game.

[[WMG:You don't need Crazy Dave, Crazy Dave needs you.]]
Think about it. He has all the seeds, all the items needed to grow plants, and places to put them. Why would he waste time with giving you the seeds when he can do it himself? Answer: you're the gardener. Crazy Dave has access to all of these items, but has no idea how to actually grow plants to defend himself. Why else would he be willing to pay so much money for the plants you grow in your Zen Garden?
* Because he's craaaaaazy?

[[WMG:The Zombies' origin]]
* Unless {{Word of God}} states otherwise, the eerie green glow from the drains around the cemetery is coming from whatever toxic substance's causing the zombies to rise from their graves.
* The infection from Left 4 Dead. Though the infection can't raise dead bodies, that's okay. All the zombies were just [[Film/ThePrincessBride mostly dead]].
* [[Film/{{Zombieland}} Mad Zombie disease]]
* [[Franchise/ResidentEvil The T-Virus.]] Your lawn was also infected, mutating your plants and allowing them to fight off the zombies.
* See below.
* NOTE: The zombies are outright stated to be undead, so they can't be TechnicallyLivingZombies. Also in the PVZ games, we have never seen an undead zombie turn a living human into another zombie.

[[WMG: Dr. Zomboss worked at Bloom & Doom]]
He created the plant and zombie seed packets you find, and was killed by one of his workers (RIP: Edgar George Zomboss, 2000-2068.) He came back to life as a zombie in 20X0 (2070) because some idiot threw an extra life item above his grave. He then started a short-term business selling the seed packets for the 49 species of plants he salvaged. After getting enough money to buy a large robot, he planted some zombie seeds and was houston-bent on taking over where Bloom & Doom used to be (before the 12/30/2068 apocalypse [AKA: Music/{{Justin Bieber}}'s Death]), now a neighborhood in the [[Franchise/SuperMarioBros Mushroom Kingdom]] named Misty Park View Meadows. He decided to invade the player's house because it was the area where his boss used to be.
* Alternatively, Dr. Zomboss is the current CEO of Bloom & Doom. He created the zombies as a way to sell his seed packets; the choices were to either buy Zomboss' seeds or have your brains eaten. This would also explain why zombies drop seed packets and Zen Garden sprouts, and how Zomboss was able to acquire plants to make the ZomBotany zombies: he simply used some of his own seeds. The fact that he attacks the player personally is because zombies cost money, and the player is wrecking his forces using seeds that were grown from the player's own plant and harvested by the player, causing Zomboss to continually lose money.

[[WMG:Ideas for plants in a possible sequel.]]
Please post examples in a "first bullet = name and basis, second bullet = effect" format.
* Tailweed (based on Devil's Tail, AKA mile-a-minute weed)
** Catches onto a zombie's foot, and the zombie has to struggle to get out of it (likely by kicking until the zombie escapes), leaving the zombie wide open for attack from other plants. Can take about 10 seconds worth of struggle total before it dies.
** Iceberg Lettuce sorta was this in PVZ2.
* Mulch-shroom (Mycetoma fungus, an infection that causes a zit-covered rash)
** Sprays Fumes/Spores that dissolve the zombie into a puddle of fertilizer, out of which another Mulch-shroom grows. Zombies who step into the puddle take damage, and are knocked over if the mushroom pops out of the ground under their feet. Upgrades to Mindbloat-shroom which acts like Hypno-shroom, but with the fume-spraying attack, and the zombie explodes when dead. However, if the fumes from either go through a Torchwood, they lose their seeding/mind-control effects.
** is the upgrade based on cordyceps fungi?
** [[http://plantsvszombies.wikia.com/wiki/Spore-shroom Spore-shroom]] basically does what the Mulchshroom would do, and Lavaguava makes the puddle.
* Salve-Shroom (Bloody Tooth fungus)
** Sprays medicine at wounded plants.
*** I thought of something like this, only I called it the Medishroom. The medishroom can be planted, and when it notices an injured mushroom, it sprays healing mist onto the plant and teleports out.
*** The Chinese version of ''2'' [[http://plantsvszombies.wikia.com/wiki/Heavenly_Peach has a plant]] that functions like this.
*** The national version [[http://plantsvszombies.wikia.com/wiki/Aloe has one too,]] but it can only target the plant in front of it.
** There's a Bloody Tooth Fungus in ''Heroes'', although [[http://plantsvszombies.wikia.com/wiki/Punish-Shroom his ability is to hurt the zombies instead of heal your plants]].
* [[IncrediblyLamePun Gun Nut]] (Gumballs, a bladed relative to Chestnuts)
** Sends [[ImpaledWithExtremePrejudice an unstoppable spear whistling down the lawn that kills all zombies in that lane.]] Due to its powerful attack, it's got a very long reload/regrow time, and costs 1000 sun. A [[ThatPoorCat cat's yowl]] or a car-alarm is heard when the spear goes off the screen. Upgrades to Shotgun nut, which shoots five spears in a fan and attacks air.
* Cucumbers could act as the icy equivalent to the Jalapeno.
** I think the Ice-shroom is that counterpart.
** No, that would be the [[http://plantsvszombies.wikia.com/wiki/Chilly_Pepper Chilly Pepper]].
* Umbrella Plants can now be upgraded to the Para-Shoot, a fusion between the old plant and Bamboo that shoots anything in the air.
* Pansies ([[CaptainObvious a pansy plant]]).
** This plant gathers suns for you automatically, but only if it's planted next to a sunflower. The pansy would cost 500 sun to plant, but after that, you don't need to worry about suns! Because of its usefulness, it's an extremely fragile plant; any zombie can one-hit kill the pansy.
* A cactus that acts like a Tall-nut/Wall-nut and Spikeweed combo
** Basically does the same job of having a ton of health, but doing damage while it's at it.
** Confirmed... [[http://plantsvszombies.wikia.com/wiki/Durian_(PvZO) in the Chinese version]]. It's also a durian, not a cactus.
** [[http://plantsvszombies.wikia.com/wiki/Endurian Also somewhat confirmed in the English version]]
** Cactus '''DID''' change in PVZ2, however, but it was was mix of spikeweed and Peashooter (with a little Bloomerang)
* Carrots
** Basically, stick underground and when a zombie walks over them, they toss them up, knocking them into a Zombie back in the row. Damages tossed zombie and any zombie it hits, but not instant kill. Plant has a recharge period before it'll toss again, leaving it vulnerable.
*** [[http://plantsvszombies.wikia.com/wiki/Spring_Bean Confirmed, sort of]].
** The actual Carrot in PVZ2 acts as a [[BackFromTheDead revival]] plant.
* Firepeaters/Burning Gattlers
** Acts as a Repeater/Torchwood combo in one plant, saving space to plant other defenses. Can be upgraded to Burning Gattlers, which fire at 6 peas every 3 seconds. These plants can also create combos when placed correctly. The peas of these plants, when going through a Torchwood, become Magma Peas, which are able to take down Gargantuars in only 13 hits.
*** [[http://plantsvszombies.wikia.com/wiki/Fire_Peashooter Confirmed, but they only come in regular peashooter form.]]
* Crusher
** This plant is an upgrade to the Chomper, but you can move the Crusher with the keyboard when you click on it. Press Space to eat zombies. You can only have one on the field at a time.
* Gigapeas
** These giant peashooters fire peapods at zombies, enabling you to hit an Imp before the Gargantuar can throw it. It also can deliver splash damage.
*** Peapod does this for it's plantfood.
* Triple Sunflora
** This plant allows for you to obtain thrice as much sun, but at the cost of durability. These plants are VERY fragile.
* Not a new plant, but just a new feature: If the fumes from Fume-shrooms go through the Torchwood, it will become sprays of flame (so it will function like a flamethrower). You know it will sound badass.
* Seed Shooter/Apple Lobber
** Sends out seeds similar to the pea-shooter, but shoots weaker shots faster/an expensive catapult that launches apples at a zombie. After a certain time, the apples would grow into a barricade. The barricade would be weaker than a wallnut, but as tall as a tall nut, and be very vulnerable while it grew.
** [[http://plantsvszombies.wikia.com/wiki/Apple_Mortar Apple Mortar is a pulting plant, but it's 3-lane plant that stuns zombies upon hit]].
* Experimental Ivy
** Taking off an idea further up, a red version of the Peashooter that spits acid globules, and tastes like garlic. An upgrade makes them mobile -- they uproot and plant themselves in the way of the nearest zombie.
* [[BananaPeel Banana Trap]]
** The zombies walk on it, slip, fall on their back (taking damage), and knock back all other nearby zombies, buying additional time to take the zombie down.
** Confirmed... [[http://plantsvszombies.wikia.com/wiki/Banana_Peel in Plants Vs Zombies Heroes]].
* Suncatcher (like a stylized Sunflower)
** Like the magnet plants capture coins and diamonds, the Suncatcher grabs falling sunbeams. Handy for fast-paced levels.
* [[http://en.wikipedia.org/wiki/Drosera Sundew]]
** An upgraded Chomper; after it finishes eating a Zombie, it'll give you 4 sunbeams.
*** [[http://plantsvszombies.wikia.com/wiki/Toadstool Confirmed, sort of]].
* Peanut (A large Peanut with the eyes of a Tallnut and the mouth of a Peashooter)
** An upgraded Tallnut that can fight back with the power of a Peashooter
** Confirmed! In ''It's About Time'', there is a new premium plant exactly named as a [[http://plantsvszombies.wikia.com/wiki/Pea-nut Pea-nut]]. It combines the functions of a Wall-nut and Peashooter. However it isn't as tall as a Tall-nut.
* Blewberry
** An upgraded Cherry Bomb, whenever a Zombie takes a bite out of it, the Zombie explodes (think like Garlic only deadlier)
*** Chili Bean is basically this, with the added bonus of a fart cloud that stuns Zombies. Sun Bean is the same thing but also gives you sun.
* Pomegrenade (Pomegranate. Which the Grenade was named after, no less)
** An instant. It costs 125 and only kills zombies on the same square it's planted on, but it explodes into a spray of seeds that hit all zombies within a 2-square radius for 20 damage each.
** [[http://plantsvszombies.wikia.com/wiki/Lava_Guava Lava Guava]] has a similar effect but not as potent.
** [[http://plantsvszombies.wikia.com/wiki/Bombegranate CONFIRMED! Bombegrenate does exactly what you said, but ]]
* Brazil Nut
** Acts like a Wall-Nut, but when it's fully eaten or crushed it explodes into a shower of seeds, dealing instakill damage on the square it's on, and deals multiple hits of medium damage in all squares directly next to it (altogether just enough to kill a conehead).
** [[http://plantsvszombies.wikia.com/wiki/Explode-o-nut Explode-O-Nut]] (yes it's now a proper plant) acts exactly like this, except it's even stronger, exploding like a Cherry Bomb on death.
* Poison Oak
** Fires leaves that do poison damage (armor isn't affected by it) its Plant Food ability is for a short time, any plant projectile (not just peas) that goes through it becomes poisonous (like the Torchwood)
** There is a Poison Oak in Plants Vs Zombies Heroes, and it's an Anti-Hero plant.
* Dead Beet
** Think of planting a pre-hypnotized zombie, I Zombie style.

[[WMG:Ideas for zombies in a possible sequel]]
Same template as the above WMG, please.
* Bombie (Zombie holding a [[FridgeLogic lit]] bomb)
** Walks at normal speed for whatever amount of time it would take an unblocked zombie to get about 1/3 of the way across the lawn. At that time, the bomb is almost ready to explode. He notices it, speeds up, and after about half the time it took for the bomb to get to the point that the zombie notices it at, (meaning he's at 2/3 of the lawn if he isn't blocked by any plants), he chucks the bomb 1/4 of the length of the lawn, which explodes when it hits the ground. [[http://i54.tinypic.com/b54p6u.jpg This chart might help your understanding.]] If it is hit by something [[KillItWithFire on fire, such as a pea that passed a Torchwood]], the bomb instantly explodes, killing the zombie and any plants and/or zombies around it. If the zombie is frozen, it won't throw the bomb fast enough for it to leave its hand, and the zombie will blow up.
** There's actually [[http://plantsvszombies.wikia.com/wiki/Blew_Zombie a zombie with a similar concept]], although with a different method of attacking.
* Zombie Goat
** Walks and eats at a fast pace, but does not take much damage. Will not attack the house if it breaches defenses.
*** So what does it do, switch to another lane and start eating from behind like a Digger Zombie?
** [[http://plantsvszombies.wikia.com/wiki/Goatify Zombie Goats]] do exist, but as the result of a BalefulPolymorph ability from ''VideoGame/PlantsVsZombiesGardenWarfare''.
* Soldier Zombie
** Carries an Assault rifle. Wears fatigues and a helmet. Explodes when hit with a fireball/jalapeno (from the grenades, you see).
*** [[http://plantsvszombies.wikia.com/wiki/Foot_Soldier Kinda confirmed]] as a playable zombie in ''VideoGame/PlantsVsZombiesGardenWarfare''.
* Posh Zombie
** Wears a black three-piece, [[HighClassGlass a monocle, a tophat, and carries a cane]], which it uses to fence away peas and move quickly. The cane is solid mahogany, so magnet shrooms can't steal it, but it can be burned away. Eats very slowly.
** Confirmed... [[http://plantsvszombies.wikia.com/wiki/Gentleman_Zombie in Plants Vs Zombies Heroes]].
* Parasol Zombie
** Carries a parasol as a shield, protecting it against lobbed plants and cob cannons.
*** Female version of above?
** [[http://plantsvszombies.wikia.com/wiki/Parasol_Zombie CONFIRMED]] as an enemy for Lost City. And yes, she's a female.
* Hypno Zombie
** Hypnotizes one plant in lieu of eating it, making it work for the zombies.
* Ball Player Zombie
** This ball-player zombie will throw baseballs at a random plant, but fire at 2 per second, meaning you'll need to have fortified defences to rid your garden of these base-runner menaces.
*** Is weak to Firepeaters.
* Baby Zombie
** Slow and weak, but crawls low, so it can't be hit by peashooters.
* Bus Driver Zombie
** Drives a bus to your garden, and once destroyed would send a cluster of imps (the zombies that ride on the gargantuar) Probably like the zomboni but slower and slightly stronger.
* Vegan Zombie (A Zombie dressed like a NewAgeRetroHippie)
** Just like a regular Zombie, only it eats plants twice as fast
** But wait, a ''VEGAN'' Zombie won't eat your brains, right?
* Gardener Zombie
** Holds a long-reaching hedge trimmer, which he uses to attack your non-defensive plants at double speed from 3 squares away. The trimmer can also bypass Wall-Nuts and Pumpkins but not Tall-nuts. Disabled by the Magnet-Shroom.
* Herbicide Zombie
** Carries a herbicide spray. When he uses it, it covers the six squares in front of him (Snapdragon range) in toxic gas, dealing constant damage to plants in it. Disabled by the Magnet-Shroom.
** Confirmed as [[http://plantsvszombies.wikia.com/wiki/Landscaper_(PvZH) a unit]] in ''VideoGame/PlantsVsZombiesHeroes''. His spray weakens a plant.
* Bug Keeper Zombie
** Carries a cage filled with zombie locusts, and will periodically release a small swarm of them into his row and adjacent ones. The locusts are similar to Zombie Chickens except that they avoid ground objects and can be blown away by Blover. The cage is plastic and thus isn't disabled by the Magnet-Shroom.
** ''VideoGame/PlantsVsZombiesHeroes'' does have a [[http://plantsvszombies.wikia.com/wiki/Locust_Swarm locust swarm]], although it's a trick and not an actual zombie.

[[WMG: The sequel will have no Zombies]]
* Plants vs Vampires
** Plant a single row of garlic and you're good.
** The planterns are also pretty game-breaking.
* Plants vs Aliens
** Search your feelings, you know it would be awesome.
*** X corn: enemy undead
* Plants vs humans
** The homeowner wreaks his revenge and sends hordes of soldiers out to destroy Zomboss's home. You play as Dr Zomboss and have to protect your fortress using zombified plants.

[[WMG: Crazy Dave is crazy because he watched his entire family get eaten alive by the undead.]]
Dave was formerly a genetic engineer with two kids and a wife. Then the zombies invaded, and Dave set to work to prevent his family being killed. He made it so the plants could be offensive and defensive against the zombies, so that you wouldn't have the problems of guns (You run out of ammo) and melee weapons (They all break).

However, Dave didn't set the plants at the right time, so the zombies broke in. He was sealed up in his lab by an auto-defense system, without his family. There were surveillance cameras throughout the house, so he could see what was going on, which included high quality images of his family being eaten alive, while being utterly helpless to help them.

After a long period of isolation in which his guilt multiplied, you arrive. Since he has near useless amounts of plants in the garden, he sells them to you. What you see of Dave when you arrive on the scene is an impossibly broken man, burdened by insane amounts of guilt and crushing despair.

I have really got to stop making really depressing [=WMGs=].
* Yeah, you should. Why does everyone keep thinking of the worst stuff possible?
** Cos they are craaaaaaaazy.

[[WMG: The zombies aren't actually after your brains.]]
They are after your potted plants. The zombies are actually herbivores, and you are a collector of rare potted plants. They smell the pollen and are enticed to devour them.

This is also why they stop to eat your plants that you are defending your house with, as a snack.

The BigNo that happens when you lose is them eating your flowers, which were probably very expensive.

Also, they say "brains" because that's the Zombie word for plants. Alternatively, the plants you own are called "Brain plants" for their oddly squishy and brain-like flowers.

When they decide to make the music video with you, it's because you've offered them the seeds of your rare plants, so they make a truce.
* Also explains where the brains come from in "I, Zombie", now that I think about it.

[[WMG: Crazy Dave is a zombie too.]]
He's just choosing to make a quick buck and selling life-saving plants to people instead of eating brains. Think the Merchant from VideoGame/ResidentEvil4. The reason he looks so un-zombie like is because um...[[WildMassGuessing he uses natural plant oils to keep his skin from rotting]]...
* [[RunningGag ...because he's craaaaaazy.]]
** [[OverlyLongGag ARGH]]!!

[[WMG: Level areas in the next game]]
The yard stays as the generic intro level, as does the night stage. However, there is a level between that and moving on where you attack Zombies in your house.

[[WMG: The Bloom & Doom Seed Co. is run by a [[TabletopGame/DungeonsAndDragons Pelorian Druid]].]]
You know it just makes a weird sort of sense. Animated plants? Powered by the sun? Generated by sunflowers? Mushrooms that can turn undead?

[[WMG: The game take place in same universe as [[Anime/PantyAndStockingWithGarterbelt Panty and Stocking with Garterbelt]] episode "...Of the Dead" several years in the future]]
You and Crazy Dave are the last humans in Romero & Carpen town. The zombies Scanty and Kneesock created are attacking your house. Crazy Dave is actually a grown-up Brief, who went insane after he realized Panty was a zombie as well.

[[WMG: The reason you, the player, can understand Crazy Dave's gibberish perfectly...]]
...Is because ''you're'' craaaaaaaaaaaazy!

[[WMG: The Piano Zombie's Piano is the real Piano Zombie. The "Zombie" is just a dummy.]]
Think about it. In one of the past updates, if the "Piano" ran over a Chili Bean, it died, just like a regular zombie. The reason it no longer happens is because it built an immunity to the killing effect. The bottom of the "Piano" is actually a mouth, which explains why the gulp noise is played when it "Runs over" a plant. It also seems to move independently, without the "Zombie" "moving it" in any way.
* OH GOD, [[VideoGame/SuperMario64 THE MAD PIANO!]]

[[WMG: The series is named after brain problems]]
A vegetable (which "Plants" are a reference to) can also mean one with severe brain-damage. A Zombie can refer to one without [[EmptyShell conscious experience, qualia, or sentience]]. As an added nod to this, plants lack brains while zombies crave them.

[[WMG: The plants are genetically modified crops]]
Bloom & Doom is a biotechnology corporation similar to Monsanto or Genentech. Crazy Dave is/was an employee working in Research and Development, and is [[MadScientist one of, if not the best genetic engineers in the industry.]] Dr. Zomboss is not only after you, but Dave as well; he is driven by jealousy and seeks to acquire Dave's genius brain.

[[WMG: Crazy Dave is a [[WMG/TimeLord Time Lord]], and Penny is his TARDIS]]
One day, they came to Earth to help the human race fight off the zombie hordes. Dave used genetic engineering to create super-powered plants for this purpose. However, he somehow became crazy and has forgotten that he's actually a space alien. However he still remembers that he has a time machine, and that his mission is to help out his neighbors.

[[WMG: Crazy Dave is actually the only protagonist]]
He has some kind of split personality and imagines himself as also being his own neighbor. [[FeaturelessProtagonist We never see]] what the {{player character}} looks like, because he/she only exists in Dave's mind. After all, he's craaaaaazy!

[[WMG: Crazy Dave and Doctor Zomboss were once coworkers.]]
Combining some earlier theories here. The two used to be a duo of scientists skilled in biological engineering, possibly working for Bloom and Doom Seed Company at one point. Their research eventually lead to the creation of the mutant plants and undead zombies (the latter were named after Zomboss). However lab accidents caused Dave to lose his sanity, while Zomboss died and turned into an intelligent zombie. Dr. Zomboss feels resentful towards society, so he raised an army of the undead (however they were rather unintelligent).

[[WMG: The [[DiscoDan Disco Zombie]] used to be a living human known as [[Characters/TheSimpsonsOtherRecurringCharacters Disco Stu]].]]
In a few of the [[WesternAnimation/TreehouseOfHorror Halloween episodes]], there was a ZombieApocalypse...

[[WMG: Chompers are a breed of [[Franchise/SuperMarioBros Piranha Plants]].]]
The resemblance cannot be a coincidence.
* The Sun-shroom also looks like a Super Mushroom.

[[WMG: In the sequel, Crazy Dave is taking a history lesson.]]
And he's keeping it a secret. Plus, it requires his time machine.

[[WMG: This game is why so many zombie-including media are so often dark and cloudy.]]
It heavily limits the amount of anti-zombie plants that can be used against them due to the lack of sunlight.

[[WMG: [[ZombieApocalypse The zombies have taken over the world]].]]
Besides [[PlayerCharacter yourself]] and Crazy Dave, [[FridgeHorror have you seen any other normal living humans around]]? Most humans have probably been killed and/or converted by the zombies, who are now running a new society of undead people. And since Dr. Zomboss has used {{time travel}} for his evil plans, he has probably had plenty of ''time'' to conquer and transform the world. Leaving behind only a few survivors such as yourself and Dave...

[[WMG:The lab experiment that gave Super Brainz powers in ''VideoGame/PlantsVsZombiesGardenWarfare 2'' was the [[VideoGame/PlantsVsZombiesHeroes Hero-Tron 5000]] prototype]]
It was an experiment to give Zombies super powers, and Super Brainz proved that it was a success. Following the success of the experiment, Dr Zomboss decided to use the Hero-Tron 5000 to take over the world... until of course, he pressed the malfunction button that made it explode, giving superpowers to select Plants and Zombies around the world. This also explains why Kernel Corn, Rose, Citron, Super Brainz, Captain Deadbeard and Z-Mech are in ''VideoGame/PlantsVsZombiesHeroes'', since it's a canon continuation.