Brain

The Brain is the center of the nervous system of the body and directs all the body's actions. It is also the favorite food of Zombies.

In Plants vs. Zombies, the zombies eat brains, which is why your house is being invaded. They appear in-game in the Mini-game Zombiquarium where it is used to feed Snorkel Zombies, the I, Zombie Puzzle Mode levels where the player plants zombies who must eat the brains at the end of every lane, and as the Zombie's version of Sun. They are also in the song Zombies on Your Lawn, where it is mentioned that they are rich in cholesterol. It is also used as a pointer for the lyrics in the music video.

As well as in parts of the game, some Zombies can be seen showing brains on pieces of their clothing or equipment. For example, the Zombie Bobsled Team has a brain picture on the front of their bobsled and the words "Brains or Bust" on the side, the Dolphin Rider Zombie speedo-type outfit has a picture of a brain on it, the Snorkel Zombie has a shirt with the legend "I love Brains," and the Flag Zombie carries a red flag with a picture of a brain.

Additionally, a message in pink slime saying "THE ZOMBIES ATE YOUR MOSE!" will appear if the Zombies get inside the player's house.

Versus Mode
The Brains were added to the game with a new key role as the Zombie's equivalent to the Plant's Sun. They are used to create zombies to attack your opponent's (Who will always be the Plants) lawn, and try to eat their brains. Much like Sun, brains will fall from the sky anywhere in the three lanes you control, and will be produced from Gravestones you make at the same rate Sunflowers produce Sun.

Trivia

 * In Bolt Creative's Pocket God, the Zombie Pygmies crave a similar looking brain.
 * The message in green slime says "The Zombies Ate Your Brains", but the human body has only one brain. The reason it is said like this is probably because people are said to have brains if they are smart, or some people just say people have brains, instead of having brain.
 * In the credits "Zombies on Your Lawn" music video, it says brains are rich in cholesterol; which is true.