What's your favorite silly game?

I've been thinking a lot about why I love Plants vs. Zombies: Garden Warfare, and it's come down to this: The game is silly. It's fun and has good mechanics with balanced classes, but lots of games can say that. I believe its art style and catchy tunes set it apart in a world of gritty blood-splatter twitch shooters and its silliness probably keeps most of the toxic players out of its lobbies, so it's fairly safe for children. So what's your favorite silly game?