The player will have control of a Lawn Mower with a peashooting plant on it where they will have to shoot all of the zombies. They can upgrade the Lawn Mower permanently into a Repeater, which will make it shoot peas in two directions, to a Threepeater, which will make it shoot in three lanes, and then to a Cattail, which will then make it shoot homing spikes and can purchase two times more to shoot faster. Additionally, the player can buy a Torchwood, which will temporarily make all the player's peas fiery, a Doom-shroom, which the player can use normally, and a Snow Pea, which will temporarily make all the player's peas frozen. Also, any sun, coins, diamonds, and presents uniquely must be collected by the Lawn Mower.
A Doom-shroom does not need a Coffee Bean to wake it up even though it is a mushroom, and the mini-game is set in Day. In this mini-game, Doom-shroom costs 200 sun, which is the total cost of a Doom-shroom (125 sun) and Coffee Bean (75 sun) during the day.
When the player pays for the Doom-shroom, the explosion will always be in the middle of the screen. The player can use the Doom-shroom even if the crater is still present.
This is possibly because the level might be harder is the player couldn't plant it on the crater.
The mini-game is based on PopCap's side-scrolling shoot 'em up game Heavy Weapon.
Heavy Weapon can be played even if the Cattail has not been purchased.
It is the only level in the whole game in which Cattail doesn't upgrade from Lily Pad.