Today CSGO is releasing the CS20 Case to celebrate the twentieth anniversary of Counter-Strike. This weapon case contains a variety of themed weapon finishes from the Steam Community Workshop and features the Classic Knife as the rare special item. Also available today is the CS20 Sticker Capsule, featuring 20 community-designed stickers.
Apart from the fantastic looking knives, the best pull has to be the AWP Wildfire. You can see all the weapons in a bit more detail here.
With this new update, they've also updated Cache and Volcano and is playable on official servers in Casual, Deathmatch, and Scrimmage