I'm going to be very upfront about this. I paid $20 for the full PC version of Plants vs. Zombies.
Now, you can give me a hard time about this--you certainly won't be the first, and you probably won't be the last. And when I heard recently that the game had gone on sale for very cheaply, I myself was a bit sad that I hadn't gotten such a good deal.
But I will tell you something else. I don't begrudge a single penny of that $20.
In Plants vs. Zombies, you defend your house from hordes of oncoming zombies. You are given a number of different plants that have different abilities--some shoot peas, some work like Venus fly traps, some instantly squash zombies. And there are different sorts of zombies, too, including disco zombies, football zombies, and swimming zombies.
Although the basic game is another variation of the "tower defense" sort of game, I find the premise to be humorous, inventive, and very much in tune with what people are interested in right now. In short, it's a lot of fun.
And while the game mechanices themselves are not tremendously cutting edge, they are clear and easy-to-play, with enough variation to keep you interested. The game does a good job of walking you through your options the first time through the Adventure level, familiarizing you with the different plants and zombies and giving you a feel for what you are able to do. And every once in a while, you get to do things a bit differently--going bowling for zombies with nuts, for example. This variety keeps things interesting, and makes the game feel more well-rounded.
What impressed me most about Plants vs. Zombies, though, is how it remains replayable even after you complete Adventure mode for the first time. In addition to the Adventure mode, there are puzzle-type games, as well as survival versions of several of the Adventure templates that challenge you to hold off the zombies for as long as you possibly can. I finished the Adventure mode rather quickly, but have found it to be a lot of fun to explore possible strategies in "Survival" mode.
Plants vs. Zombies also has achievements, as well as a Zen Garden where you collect pet plants that drop off of zombies that you kill. Both of these features--while not tremendously original--do offer other lighthearted incentives to keep coming back to the game.
Of course, there are a few things I think I would do differently if I were the game designer. I would make the trial version a bit shorter. I feel like I was able to play through almost 2/3 of the Adventure part of the game before I finally had to pony up my money. And then I felt a bit let down that there wasn't more to the Adventure section once I finally did bust out the credit card.
Adding to this feeling was the fact that the game advertised that it had "50 levels" in Adventure mode. Plants vs. Zombies organizes its levels into groups of 10, giving a number to both the individual level and the larger group. So the first level is level 1-1, then comes 1-2, then 1-3, etc. But because each group of 10 is given a number as well, I misunderstood what "50 levels" meant, and thought that there were 50 groups of 10 sublevels. So when, after level 5-10, I was told that I had defeated Adventure mode, I felt a bit cheated.
That said, though, the game is so much more than the Adventure mode, and even several months after purchasing the game, I still find myself coming back to it several nights a week--even if just for 15 minutes or so to play a few levels and unwind.
Plus, of course, I still need to catch that elusive Yeti zombie...