Complete Adventure mode.

Collect all 49 plants (including plants from Crazy Dave's shop).

Defeat your first Gargantuar.

Plant your first 10 peashooters.

Blast 10 zombies at once with a Cherry Bomb!

Win any level after all lawnmowers have been used.

Go trunk diving and spend at least $25,000 on Crazy Dave's Twiddydinkies.

Stop the horde using only the Sunflower, Wall-Nut, and Chomper on any level.

Complete a nighttime level without planting any Mushrooms.

Complete a daytime pool level without using peashooters of any kind.

Defeat a normal roof level without using any catapult plants.

Complete a daytime level by planting only Mushrooms and Coffee Beans.

Defeat 2 Gargantuars with Corn Cob missiles in a single level.

Bowl over 5 zombies with a single Wall-Nut.

Hypnotize the lead dancer zombie.

Get to a streak of 10 in I, Zombie Endless.

Get to a streak of 15 in Vasebreaker Endless.

Beat all 19 mini-games.