Steam's autumn sale is now live with all kinds of discounts on games old and new.

Current flash sales — deals expiring within hours — include 75 percent discounts on Limbo and Star Wars: Knights of the Old Republic 2, to $2.49 each. While the Serious Sam Complete Pack itself isn't on sale, the games within it are all available at a 75 percent discount. Here are the deals running for the next 48 hours:

• XCOM: Enemy Unknown: $33.49 (33 percent off)
• Magic: The Gathering - Duels of the Planeswalkers 2013: $4.99 (50 percent off)
• The Walking Dead: $12.49 (50 percent off)
• Darksiders 2: $16.99 (66 percent off)
• Age of Empires 3: Complete Collection: $9.99 (75 percent off)
• Terraria: $3.39 (66 percent off)

Plenty of indie games are also on sale, with discounts ranging between 40 and 75 percent. World of Goo and Cave Story are being offered for $2.49 each, 75 percent off their regular price.

The sale will run from today through Cyber Monday, Nov. 26.