Gargantuar

Gargantuars (Gargantuar Zombie in Plants vs. Zombies Adventures) are the third strongest zombies in Plants vs. Zombies (only Dr. Zomboss and the Giga-gargantuar are stronger, and the Giga-Football Zombie has the same amount of health), taking two instant kills to destroy. It is the 23rd zombie encountered in Adventure Mode. Not only does this massive land zombie have high health, but it also crushes the player's plants instead of eating them. Because the Gargantuar can crush plants, it is capable of destroying Spikerocks and Spikeweeds (Spikerock takes nine crushes of damage though). Upon dying, Gargantuars drop their telephone pole, wild life pole, or zombie, roar, sway, and fall over. Once a Gargantuar has lost half of its health (or been attacked by an instant kill), it will throw its Imp if it is not more than halfway to the player's house.

Suburban Almanac Entry
 Gargantuar 

Gargantuar is a gigantic zombie.

Toughness: extremely high

When Gargantuar walks, the Earth trembles. When he moans, other zombies fall silent. He is the zombie other zombies dream they could be. But he still can't find a girlfriend.

Plants vs. Zombies
The Gargantuar absorbs 150 normal damage shots and its appearance changes after 50 and 100 normal damage shots before dying at 150 normal damage shots or 2 instant kills. The Gargantuar throws its Imp at 75 normal damage shots, or 1 instant kill.

Plants vs. Zombies Adventures
After 50 damage (or one instant kill) the Gargantuar Zombie will throw the Imp. After 150 damage, the Gargantuar Zombie will be defeated. The only degrade is at 50 when its Imp is thrown, no bandages appear on the Gargantuar Zombie.

Plants vs. Zombies

 * Adventure Mode: 5-8, 5-9, 5-10
 * Mini-games: Column Like You See 'Em, Dr. Zomboss's Revenge, Buttered Popcorn, Heavy Weapon, Heat Wave, BOMB All Together!, Zombie Trap
 * Puzzle Mode: Ace of Vase, Vasebreaker Endless, Me Smash!, Last Stand: Roof, Last Stand: Endless
 * Survival Mode: all Survival (Hard) and Survival (Endless) levels
 * Co-op Mode: Co-op Bowling, all Co-op Hard levels, Co-op Zomboss, Co-op Endless
 * Others: Versus Mode

Plants vs. Zombies Adventures

 * Zombitorium Manor: All levels

Strategies
You can delay a Gargantuar with Spikerocks, which take nine smashes before they disappear. Cheap plants like Puff-shrooms are also a good choice, as they have fast recharge and cost no sun which makes them good emergency delayers. It is advised that you attack it with at least one instant, or else it may do a lot of damage to your vital defenses. Winter Melons are quite useful against it, especially in Survival: Endless. Although Chompers cannot eat a Gargantuar whole, they can keep biting at it, doing two nds per bite, making them good for weakening them. Hitting a Gargantuar with a Squash followed by a Jalapeno kills it fast, and prevents the Imp from doing serious damage. A charged Potato Mine will deal damage to the Gargantuar when it crushes it. Hypno-shrooms do not work against it, because it does not try to eat anything. However, a hypnotized Imp can eat a Gargantuar without dying. Rows of Gloom-shrooms adjacent to his path will work as well. In the Survival Mode Pool levels (especially Survival: Endless) you can stagger it a bit so that Gloom-shrooms in the Pool kill Gargantuars before they reach ones on dry land. Another way to take out a Gargantuar is to use two Gatling Peas and a Torchwood. You can also kill a Gargantuar without making it launch its Imp. You have to have good defenses, though. First, let your plants damage it until its arm gets a patch. Once that happens, quickly use an Instant Kill. It will die and the Imp won't even be thrown.

Probably the most useful strategy for Gargantuars, working well in both Dr. Zomboss's Revenge and Column Like You See 'Em, is using two Jalapenos, one to activate the Imp and another one to take them out without major damage from the Imp.

I, Zombie
In the I, Zombie level Me Smash!, these are useful in hard rows without multiple Squashes, although occasionally a single Squash and a Kernel-pult with other offensive plants can kill it too.

Vasebreaker
In Vasebreaker, save some Squashes to get rid of these zombies, though Potato Mines work as well. There will be a Gargantuar but it might be difficult as the Squashes will go away after some time and clicking randomly until the Gargantuar appears might outnumber your other lanes.

Giga-gargantuar
The Giga-gargantuar is the second most powerful zombie in the game (only surpassed by Dr. Zomboss), found only in Survival: Endless, Survival: Day (Endless), Survival: Night (Endless), Survival: Fog (Endless), Survival: Roof (Endless), Co-op Endless and Last Stand: Endless. It has double the health of a regular Gargantuar.

Plants vs. Zombies

 * A Lawn Mower or a Roof Cleaner can kill a Gargantuar, despite the size of the Gargantuar. When it is killed by one, the Gargantuar turns into a puff of smoke even though the Gargantuar is not mechanical.
 * This could be because the Gargantuar has no "head falling off" animation. It would also seem odd if it dies the normal way (drop club, stagger, fall down and die) when hit by a lawn mower (actually both seem weird, but exploding seems better and more appropriate than the normal death).
 * Despite the Almanac saying that the Earth trembles when Gargantuar walks, the whole screen does not shake when he takes a step.
 * The Almanac probably says that to emphasize the Gargantuar's power and control.
 * In the I, Zombie level Me Smash!, the Gargantuar squashes the brain instead of eating it.
 * However, there is a biting sound when this happens. The same sound is also played after it kills a plant. This is because the Gargantuar has no eating animation.
 * This is also played when a Zomboni, a Catapult Zombie, or Dr. Zomboss' Fireball or Iceball attack kills a plant, or when the Zombot's foot or camper crushes other plants.
 * According to its Suburban Almanac Entry, the Gargantuar is the only Zombie who is looking for love.
 * The Gargantuar is the second most expensive zombie in I, Zombie, costing 300 Sun.
 * The only zombie which costs more in I, Zombie is the Dancing Zombie, which costs 350 sun.
 * Both use other Zombies to attack.
 * If the Gargantuar is killed by an explosive and hasn't been able to throw its Imp, the body of the Imp will also disintegrate inside the trash can and then its head will fall onto the pile of ash the Gargantuar has turned into.
 * If the Gargantuar is killed (not by explosive instant kills besides Potato Mines) while the Imp is still alive, the Imp will recede back into its trash can.
 * The Gargantuar will not hit other zombies that have been affected by a Hypno-shroom. The Zombie will eat the Gargantuar, but they usually cannot kill the Gargantuar before he goes away because Gargantuar's high health.
 * If a Chomper manages to kill a Gargantuar, it will show the chewing animation with a normal zombie's arm sticking out.
 * The Gargantuar, the Zomboni, Dr. Zomboss, the Giga-gargantuar, the Catapult Zombie and the Squash Zombie are the only zombies that can crush plants.
 * If a Gargantuar is killed while slowed by some sort of ice plant right at the starting point you will be able to see the corpse while you are picking plants (Survival Mode only.)
 * After the Gargantuar has half of its health gone, bandages will appear on its body.
 * The Gargantuar smashes and crushes the plants, similar to what the Squash does to zombies.
 * Gargantuars can have one of three different clubs: a telephone pole, a wildlife crossing sign, or another zombie.
 * The zombies that the Gargantuars use have cut ties on their clothes.
 * Gargantuars only use normal zombies as clubs.
 * Their hand's graphics seem to be designed specifically for the telephone pole, as for other clubs their fingers partially overlap the sprite of the wildlife crossing sign or Zombie respectively.
 * The name "Gargantuar" likely comes from its gargantuan size or possibly as a reference to the Toho movie "The War of the Gargantuas".
 * It also may also be a reference to the fictional French giant Gargantua.
 * Gargantuars can only throw its Imp five squares away from the right side of the screen. If a Gargantuar loses half of its health at the fifth square, it can't throw an Imp.
 * The Gargantuar is one of the two zombies that have a Giga form. The other is the Football Zombie.
 * The Gargantuar is one of the three zombies that comes in groups, the other two are the Zombie Bobsled Team and the Dancing Zombie with its Backup Dancers.
 * When a Gargantuar throws an Imp while it is frozen or slowed down, the Imp will also be slowed down.
 * The Gargantuar, the Giga-gargantuar, the Bungee Zombie, the Balloon Zombie above the pool, the Zomboni, the Catapult Zombie, the Catapult Baseball Zombie and Dr. Zomboss are the only zombies whose heads don't fall off when killed or defeated.
 * When the Gargantuar smashes a plant, the whole screen shakes.
 * The screen also shakes when the Gargantuar's dead body hits the ground.
 * It also happens when the Squash squashes any zombies.
 * This also occurs when Cob Cannon's cob explodes.
 * When using the Action Replay on the DS version, a glitch may occur in which when the zombies are viewed, the Gargantuar will be seen without a head, the Imp at its back, and its legs.
 * The Imp on the Gargantuar holds reins tied to the Gargantuar's collar but when he throws the Imp the reins disappear.Frozengargantuarsfallingover.png.]]
 * A rake alone will not kill a Gargantuar. It will deal one instant kill of damage, but he will throw the Imp.
 * The Gargantuar's roar is the same roar used by Dr. Zomboss when his Zombot is destroyed.
 * It takes six hits in Co-op Bowling.
 * The Zombot looks like it is based on a Gargantuar, considering the toughness and appearance of both zombies.
 * The Gargantuar, the Balloon Zombie and the Screen Door Zombie are three of four zombies that appear in I, Zombie levels, but not in I, Zombie Endless. This is probably to keep the player from making the puzzle too easy, due to the fact that these three are super-effective against the plants in the level. However, the normal Zombie is also omitted to make the game more challenging in another way, for a normal zombie can sometimes manage to clear a line with a single offensive plant, while the Imp cannot in most cases, unless the offensive plant is a Spikeweed or (sometimes) a Kernel-pult in the rightmost column.
 * It is possible for a Gargantuar to be damaged by a Spikeweed or a Spikerock, if you plant it under the Gargantuar.
 * If a sleeping mushroom is squashed by a Gargantuar or Dr. Zomboss, the mushroom will become a flattened woken version of the mushroom.
 * Gargantuar's toes are visible at some point. They stick out of its shoes. This hole in the shoe appears with the first bandage, when a half of its health had gone.
 * The Gargantuars may be a reference to Shrek since they look like ogres.
 * Since Gargantuars don't eat, it is odd that the eating sound is played if it successfully invades the house.
 * Despite the fact that the zombies in the game were once humans, it doesn't make sense how a Gargantuar could have a been a human due to its massive size.
 * It is possible that it could have gotten mutated from Dr. Zomboss before the events of Plants vs. Zombies.
 * As seen in the concept design for Gargantuar posted on the Plants vs. Zombies Facebook page, the Gargantuar was going to be a much more muscular zombie with short legs. His telephone pole is still present, however.
 * Gargantuar, Giga-gargantuar, Giga-Football Zombie, Pharaoh Zombie, Tall-nut Zombie and Dr. Zomboss are the only zombies that can survive an instant kill.
 * The Gargantuar has a collar around its neck.
 * You can kill a Gargantuar before he launches his Imp, if you find two fully-charged instant kills or explosives.
 * The Gargantuar can only have two bandages.
 * It is unknown why the Gargantuar throws its Imp. It is possible that it is so angry at being wounded, it needs somebody to take its anger on, or simply on Dr. Zomboss' orders.
 * When a Gargantuar squashes a Sunflower in the I, Zombie level "Me Smash!", all the sun comes out, unlike the other zombies in I, Zombie, as they eat the Sunflower while sun comes out.
 * The Gargantuar and Imp may be a reference to Freak the Mighty, where Freak rides on Max's shoulders like an Imp rides on a Gargantuar's back.
 * Gargantuar's shirt and shoes gets torn up at every degrade.
 * When Dr. Zomboss puts down a Gargantuar, the Gargantuar is actually taller than the Zombot's hand. The Gargantuar then seems to appear out of nowhere.
 * This also happens on versions of the game that have bushes on the far right of the lawn.
 * The Gargantuar stops moving for a while when it throws an Imp.
 * If a Gargantuar dies before the Imp is tossed, then the Imp will disappear into the trash can.
 * This is because there is no died with Imp on back animation.
 * It is weird that in the DS version, plants will be crushed before Gargantuars finishes crushing them. This makes it harder to defeat in the DS version.
 * This also happens in the DSiWare version.
 * Despite its heavy weight, the Roof can still hold the Gargantuar and doesn't break when the Gargantuar falls or smashes a plant.
 * It is unknown how it can fit inside the vases in Vasebreaker.
 * Its wildlife crossing sign seems to have a duck on it.
 * Sometimes, in the DSiware version, the Gargantuar will change its weapon when it smashes a plant.
 * This also happens in DS Vs mode.
 * If you hack Wall-nut Bowling 2 to have a Gargantuar, a Giant Wall-nut can kill it in one hit.
 * The HD Gargantuar has a naked Imp.

Plants vs. Zombies Adventures

 * Though it still has its pole, in the "Choose Your Seeds" screen of Road Trip levels, it appears without its pole.
 * When a Gargantuar Zombie is defeated with the Imp still riding in this game, the Imp will fall out of the trash can and onto the ground.
 * This isn't so if it gets burned.
 * Sometimes the Gargantuar Zombie will not throw its Imp. This is because the location of where the Gargantuar Zombie is throwing, this is where the Imp's location will also be. This being so, when the Gargantuar Zombie throws the Imp, the Imp will take damage, sometimes killing it, and not taking the flag.
 * In Brainball, there is no known way to prevent any attack from Gargantuar Zombies because of its Imp throw landing very close to a target building. You can easily use a wave of Barrel Zombies if the Imp does not reach your target.