Dark Ages - Night 20

"A question for you, my Ignoble Foes! Hast thou noted how violent thine plants become upon consuming Plant Food? Perchance, has thou wondered what Plant Food is truly made of? Verily, I shall tell thee. It's zombies! Plant Food is made out of zombies!"

- Dr. Edgar Zomboss

Dark Ages - Night 20 is the last level in Dark Ages. Dr. Zomboss makes his appearance in this level with his Zombot creation called Zombot Dark Dragon. Being a boss battle itself, the player is forced to beat Dr. Zomboss and his plants in order to win the level. To beat the level, the Zombot Dark Dragon must be defeated. When this level is finished for the first time, the player gets the Dark Ages Trophy.

Difficulty
The Zombot Dark Dragon can summon random zombies from random tiles. One fact is that when it reaches the second stage, it can summon up to three Dark Ages Gargantuars on the lawn. It can multiply, however, if not monitored properly. As well as this, many of the plants given are somewhat weak and can be thwarted by the Jester Zombie throwing back their projectile. Additionally, the Wizard Zombie if not watched carefully, can easily ruin the player's whole set up quickly, leaving him or her defenseless. If the player does not have a good strategy prepared, the Zombot Dark Dragon will demolish his or her lawn.

Strategies

 * Note: The Magnet-shroom will always be boosted, even if it is not in the Zen Garden. This is to help deal with the Zombot Dark Dragon's weakness.
 * You can only ever have one Magnet-shroom at any given time in this level. After its boost wears off, dig it up, and likely it will be one of the next four plants to arrive on the conveyor-belt. Use this to your advantage, and plant it to stun the Zombot Dark Dragon before it attacks and summons zombies. This is also useful for dealing with Knight Zombies and Wizard Zombies simultaneously.
 * Note: The seventh column can only be targeted when the dragon spits fires with Imp Dragon Zombies. Take advantages of this for Puff-shrooms.
 * When the dragon's cheeks puff up, it means its about to breathe fire (it is a variant of the charge attack). When this happens, immediately give Plant Food to the Fume-shroom only or plant Magnet-shroom as they can stop the Zombot. Do not hesitate and do not make a mistake or your plants will be burned.

Phase one (full health)

 * Summoned zombies
 * Peasant Zombie
 * Conehead Peasant
 * Buckethead Peasant
 * Jester Zombie
 * Wizard Zombie
 * Imp Dragon Zombie
 * If you get Magnet-shroom, use it immediately, then dig it up to use it again but only if Buckethead Peasants come in large numbers. Be sure to place it on where the Zombot Dark Dragon is to damage it.
 * Immediately plant as many plants as you can to kill the Wizard Zombies quickly. Remove the Puff-shrooms when you see Jester Zombies. Pea-nuts make an excellent decoy in this level in order to lure the Jester Zombie.
 * Kernel-pult is not compulsory, it will only help you as the Last Resort or stun the zombies, especially Wizard Zombies. However, its projectiles can be deflected by Jester Zombies, so make sure that there is at least one Fume-shroom on each lane.
 * Imp Dragon Zombies are not a threat, except when the Zombot Dark Dragon use its charge attack. Kill them quickly.
 * Note: Each lane should have at least one Fume-shroom in case of Jester Zombies.

Phase two (one-third of health is gone)

 * Summoned zombies
 * Peasant Zombie
 * Conehead Peasant
 * Buckethead Peasant
 * Imp Dragon Zombie
 * Dark Ages Gargantuar
 * Imp Monk Zombie
 * Dark Ages Gargantuars will be summoned during this phase, and are considered as the largest threat. Use Fume-shroom's Plant Food Upgrade to weaken the Gargantuars, as once it is pushed back to the very front of the lawn, the scorched tiles will burn it. However, Zombot Dark Dragon will become more relentless in this phase and it can call more than one Dark Ages Gargantuar in some occasions. Be sure to dispose all of them before they could cause more serious havoc.
 * Wizard Zombies and Jester Zombies will not be summoned in this phase, therefore, you do not need to worry about them.
 * Zombot Dark Dragon will use its fire breath ability here, removing all of your plants in a 2x2 row. This is identical to its charge attack from its first four creations. But it will not allow you to replace lost plants immediately.
 * Fill Puff-shrooms on the sixth and seventh column to attack Dr. Zomboss.

Phase three (two-thirds of health is gone)

 * Summoned zombies
 * Conehead Peasant
 * Buckethead Peasant
 * Imp Dragon Zombie
 * Knight Zombie
 * Wizard Zombie
 * Wizard Zombie appears again in this phase, and Dark Ages Gargantuars will not be summoned anymore. Watch out for Wizard Zombies and stall them with Plant Food or by planting extra plants.
 * Knight Zombies are exchanged for Dark Ages Gargantuars. Use the boosted Magnet-shroom in this phase more often.
 * Use all remaining Plant Foods on the Puff-shrooms if you can finish the Zombot with it.

Aftermath dialogue
"I have found no evidence that Plant Food contains zombies or zombie byproducts."

- Penny

"Phew! Plants shouldn't eat zombies who eat plants. Except Chomper. He has to. Dude needs the fiber."

- Crazy Dave

Trivia

 * The Zombot Dark Dragon will always kill Magnet-shroom first with its fireballs.
 * Before starting the battle, Dr. Zomboss said Plant Food is made out of zombies which is somehow true as zombies drop Plant Food.
 * Chomper is referenced after the battle, even though it did not appear in the game at the time of Dark Ages - Part 2's release.
 * Chili Bean (some translations only of Pirate Seas - Day 25), E.M.Peach (Far Future - Day 11), Hypno-shroom (Far Future - Day 25), Pea-nut (Dark Ages - Night 18), and Homing Thistle (Big Wave Beach - Day 21) are the other only plants mentioned in any dialogue in Plants vs. Zombies 2: It's About Time.
 * This is the first of two Zomboss fights where the player always gets a boosted plant (in this case Magnet-shroom) and a premium plant (in this case Pea-nut) at one point.
 * This is also the only Zomboss fight where the player faces him on Level 20, instead of Level 25, or Level 32.
 * Additionally, this boss is the first creation to neither appear to be quadrupedal nor be fully visible.
 * Unlike most Zomboss creations, the charge attack does not include the creation performing a running dash across two adjacent rows.
 * The charge attack is also unique for disabling affected tiles from immediately (lasts for a few seconds) allowing plants to be placed on them.
 * The player can only have five Kernel-pults, ten Fume-shrooms, ten Pea-nuts, ten Puff-shrooms, and one Magnet-shroom on the lawn.
 * When completing this level for the first time, the trees on the map will be grown.