Pour a cup of coffee, put on some headphones, launch Peggle , and try to beat the "Extreme Fever" challenge. When that final peg lights up and the orchestra swells, you’ll realize why this collection is burning up the retro charts.

From the early 2000s to the rise of mobile gaming, PopCap Games was synonymous with quality. They didn't just make games; they defined the "casual" genre. Today, collections of their classic titles are trending "hot" once again. But what is it about these decade-old puzzles and strategy games that keeps them relevant?

Valve frequently bundles 15+ PopCap games for under $20 during sales. Wishlist the "PopCap Complete Pack." Warning: Ensure the version you buy includes Plants vs. Zombies GOTY Edition , as standard versions sometimes lack the zombie bowling mini-game.