Adventure Mode is the first available mode in Plants vs. Zombies. There are five groups of ten levels, which are Day, Night, Pool, Fog, and Roof; each with their own characteristics. A new plant is unlocked and added to the player's roster at the end of most levels.
In Adventure Mode, the player starts out with only a Peashooter. The fifth level in each area is a Bonus Level, which takes the form of a mini-game. The tenth level of every stage is a Conveyor-Belt Level. Every fifth level, except for Level 5-5, is later unlocked as a mini-game or Puzzle Mode level. During level 3-2, the Mini-games mode is unlocked, and Puzzle Mode is unlocked during Fog level 4-6.
Replaying Adventure Mode
Once Adventure Mode has been beaten once, the Silver Sunflower Trophy is obtained, more Mini-games (at least one, but a maximum of three) and Puzzle Mode levels are unlocked, and Survival Mode is unlocked. There is an option to replay Adventure Mode; however, Crazy Dave will choose three random seed packets in the player's seed slots, each of which is different in every level and can't be replaced or removed, but can be altered on most versions. Bonus Levels will be replaced with their corresponding Mini-game or Puzzle Mode counterpart, and a Money Bag containing $250 Coins will be dropped by the final zombie each level instead of a seed packet or item (except 4-5, in which the bag only contains $100), though notes are still dropped. While replaying Adventure Mode, the Zombie Yeti can be found in level 4-10. Almost every level has an extra flag, with a few exceptions, like 1-10, 2-5, 2-10, 3-10, 4-5, and 5-10. The game will only record the number of times the player completed adventure mode up to 2,147,483,647; after that, the game cannot store the value of the number of times the player has completed adventure mode.
Basic Area Overview
At the end of first through third and fifth through eighth levels, a new seed packet is obtained.
At the end of the fourth level, an item is obtained.
The fifth level is a Mini-game, and a seed packet is obtained at the end of it.
A note from the zombies is obtained at the end of the ninth level.
The tenth level is a Conveyor-Belt Level, and a seed packet that is important for the next area is obtained at the end of it. At the end of level 5-10, the player just gets another note from the zombies saying they give up and the Silver Sunflower Trophy at the first time.
Unless otherwise specified, each level has one extra flag after the player finishes Adventure Mode.