Plant Budz 98 is what happens when a virtual pet game is taken way too far. Imagine playing WarioWare, Doom, and R-type with your Tamagotchi on a Windows desktop. You'd get something close.
It starts innocently enough. You've got a virtual desktop. You've got a pet. You feed it, play with it, watch it grow. Normal stuff.
Then your Pig evolves and suddenly you're bashing through obstacles in an endless runner. Your Fish becomes a side-scrolling shooter with a Starfox-style level progression, unique bosses, weapon upgrades, the works. Your Cat drops you into a 2.5D first-person shooter with sprawling levels. Your Robot hands you three simultaneous minigames and a timer and wishes you luck.
Oh, and you can replay any game as any pet. They all play differently. There are unlockables. It's got a soundtrack that'll have you grinding your armrest.
We may have lost the plot a little. You'll love it anyway.