Digger Zombie

The Digger Zombie uses its sharp pickaxe to dig through the ground towards the left side of the lawn, allowing it to attack the player's plants from behind. It will pause for a few seconds before proceeding to eat your plants once it has resurfaced. It is not present on Roof levels. Without advance preparation, they have the potential to do devastating damage to rows of plants. It is first encountered in the Fog levels. Note that as it eats the plants from left to right, it never makes an attempt to get into the Homeowner's house.

Overview
Absorbs 15 of normal damage shots. Appearance changes occur after 4, 5, and 10 normal damage shots and dies after 15 of normal damage shots.

Strategy
You can use Magnet-shrooms to steal the zombie's pick so it can't dig. Also, try using Potato Mines, as they explode if he digs underneath them. Alternately, place Gloom-shrooms or Spikerocks at the back of the lawn, or use Split Peas, Starfruit, and/or Cattails to kill it. You can also use Pumpkins on your back row allowing your other plants more time to kill it. Instants, especially the Jalapeno, are good in emergencies.

A Magnet-shroom that has just refreshed may snatch the Digger Zombie's mining pick while it is in the middle of your plants, forcing him out of the ground in an inconvenient location. Having a Pumpkin, Ice-shroom, or Jalapeno available can counter this situation.

In Survival: Endless (or similar levels with many diggers), the Gloom-shroom (you can use only two to save space for other plants) or Spikerock setups are the best to take care of them, because your Magnet-shrooms, Split Peas, Cattails, and/or Starfruits won't be able to keep up (making them almost useless and creating a necessity to remove them and saving space.)

Note that explosive Instants can kill Digger Zombies while they are mining, so Doom-shrooms make very short work of them due to the large area, although other Instants like the Squash do not work while they are underground. However, the easiest (but slowest) way to take care of them is to use Potato Mines, due to them exploding as soon as a Digger Zombie goes beneath one, and how they can be set up in advance. Also, if a Chomper is planted on the square one emerges from, it can eat it.

In I, Zombie, you can use this zombie to destroy lanes that have no offensive plants that attack other lanes or backwards (Threepeaters, Starfruit, Split Peas), although iconvenient, they can still be used in these rows. Rows with Squashes, Magnet-shrooms, or Potato Mines are effectively impervious.

Trivia

 * Even after the Digger Zombie surfaces, a Magnet-shroom can still steal its pickaxe.
 * The Digger Zombie (if it reaches the left side of the lawn), the Zombie Yeti, the Bungee Zombie, and Dr. Zomboss are the only zombies that doesn't target the your house.
 * The Digger Zombie also has the slowest chewing rate of all zombies; however, its bites do twice the damage of that of other zombies.
 * If the Digger Zombie is forced out of the ground via Magnet-shroom, it will walk at normal speed.
 * The Digger Zombie is the only zombie that will not change directions when in contact with a Hypno-shroom, it will simply continue going forward while hypnotized, unless the the player steals its pickaxe while it is digging.
 * The Digger Zombie's helmet is available in the Xbox Live Marketplace as a hat for your avatar. It costs 160 Microsoft Points.
 * Digger_Potato.jpg Digger Zombie must eat defensive plants with ladders on them, as the ladders are on the opposite side from it.
 * A Digger Zombie can eat an unarmed Potato Mine while underground.
 * Even without its pickaxe, the Digger Zombie's death animation is similar to its original one that has a pickaxe.
 * A Digger Zombie can still eat your brain when a Magnet-shroom steals his pickaxe.
 * The Digger Zombie can be killed by an explosive when it is still underground.
 * The Digger Zombie has the weakest headwear and also the weakest armor in the game.
 * The Digger Zombie's helmet seems to be made of plastic, because a Magnet-shroom can't steal it.
 * The Digger Zombie (while digging), the Ladder Zombie, the Balloon Zombie (while on its balloon), the Gargantuar, the Zomboni, and the Catapult Zombie are the only zombies that can get past a Tall-nut by itself without eating the plant.
 * It is unknown how the mining helmet can protect the Digger Zombie from projectiles and some plants like Spikeweed, as they mostly hit the other body parts except for Lobbed-shot Plants.
 * Along with NewsPaper Zombie, he is one of the two zombies that could have a question mark over their head.