Remember those "tower defense” browser games you would play in middle school when you were supposed to be typing up the rough draft to your English paper? Plants vs. Zombies follows the formula of those wildly popular defense games, while adding a few unique twists of its own.
The dead are coming back to life and are hungry for brains, and you just happened to have purchased the house directly across the street from the local cemetery. Lovely. Fortunately for you, you happen to possess a variety of plants with different traits and abilities with which to defend yourself. If you’ve played other games from the genre, you’ll find Plants vs. Zombies is as straight-forward as it gets: zombies try to cross your lawn to get to you, and you position various plants on your lawn to take out the incoming zombies before they can make it to your front door. Simple as it may sound, there is an element of strategy necessary to make it past all 50 levels of the game.
One could best describe PvZ as a giant rock-paper-scissors game. Zombies will put on traffic cones and buckets to protect themselves from your Pea Shooters, but you can place Wall-Nuts in their paths to trap them in the line of fire long enough for your Pea Shooters to take them out. To counter those, the undead will start carry poles to vault over Wall-Nuts, but you can prevent that by planting Tall-Nuts instead. And to get past those, the zombies start digging tunnels underneath your plants, and devour them from behind where they can’t defend themselves from, prompting you to start placing Split Peas to kill zombies coming from both the front and back of your lawn. Occasionally, your neighbor, Crazy Dave, will stop by to offer advice, sell you items that increase the number of seeds you can carry, new plant types, modifications to plants you already own, or he’ll just break up the action a bit by playing a mini-game with you.
Since it's a casual game, PvZ is very easy to get into. Even if you're a hardcore gamer, you'll still find it addicting as all hell, and it's a great way to get a non-gamer in on the gaming scene.