Bet you'll never guess what July's best-selling PSN game was. Spoilers: Shadow of the Colossus.

Team Ico's classic adventure edged out The Last of Us for spot #1 on Sony's official charts, mostly thanks to a summer sale that saw the giant-monster-stomping game sell for $10 digitally.

We don't spend a ton of time talking about sales data here on Kotaku—because, honestly, sales are kind of boring—but this is particularly interesting because Shadow of the Colossus is a PS2 game. It came out in 2005. Almost two console generations ago! Yet it outsold everything else on the PlayStation Network last month.

Potential hypotheses we can draw up here:

1) Shadow of the Colossus is a good game.

2) People like buying games that are on sale.

3) Classic games > Modern games?

We'll take these to the lab and get back to you.