PlayStation Plus members will be able to download full versions of Tomb Raider: Underworld and PSN's Marvel Pinball this month, along with three PSone classics from the Spyro franchise. Underworld and Spyro are available tomorrow, December 6, while Marvel Pinball goes gratis on December 13.

After getting hooked on Marvel Pinball, be sure to check out the Captain America and Fantastic Four add-on tables, which will be available for 50 percent off. Head on over to the PlayStation Blog for a full list of December discounts.