Sony is listing a new deal every day leading up to Christmas day as part of the "12 Deals of Christmas" holiday promotion. The holiday promotion started on November 30, alongside a "Games Under 15 Euro for Christmas" promotion for PS3 and PS Vita titles.
The 12 games for Christmas deals only last 48 hours after their announcement so you'll have to be quick to snatch up the best deals. On November 30, the promotion started with a discount to Metal Gear Solid V: The Phantom Pain, which was listed on the PlayStation Store for 34.99 instead of 69.99, essentially taking 50% off of it's digital price. The same 50% discount was available for the PS3 version too.
A number of great deals have been posted over the last couple of weeks but we're now onto deal 7 of the 12 days of Christmas and it lists Assassin's' Creed Syndicate (The new one!) at a discount. The base price of Syndicate is 69.99 but it can now be picked up for 49.99 for two days. The season pass has also had a discount and now sits at 19.99 instead of 29.99. If you want to save even more, you can purchase the Gold edition, which has a huge $45 discount. Usually at 99.99, it can now be picked up for 54.99 for the next 48 hours.
Make sure to keep an eye on the Sony blog to see more Christmas deals as they are posted.