Humble Bundle promised to add more games to its enticing Humble 2K Bundle, but I didn’t think it would be anything of this magnitude. Now I might have to pick it up. Indeed, the entire lineup of classic X-COM games, from before publishers dropped the hyphen, have been added to the list, bringing the total number of games from eight to 13.

XCOM found a new audience in 2012 when XCOM: Enemy Unknown became a surprise hit. Fans of the classic series lashed out at 2K Games for reinventing it as a third person shooter, and 2K Games acquiesced with this wonderful game. The third-person shooter went on to lackluster sales and financial disaster. If you haven’t had the chance to see what all the fuss was about, then this is the best option to see where all that passion was coming from.

X-COM UFO Defense is the clear winner of the bunch and is a masterpiece on all levels. It’s a little tough, but even the newer game failed to recreate the same creepy horror vibe found in the sprites and dated graphics. The other four games are all solid attempts to expand and build on its core ideas, but none do it quite as well as Enemy Unknown did.

Just don’t expect the same smooth interface, and you should be all set. You’ll have to pay the average price if you want to unlock the bundle within a bundle, and that currently sits at $8.