The Winter Offensive Weapon Case is a CS2 weapon case introduced 10 years ago on 18 December 2013 as part of the "Winter Offensive" update. The weapon case contains CS2 skins from The Winter Offensive Collection.
This case was the first community-made case featuring some of the most popular skin designs from the Steam Community Workshop.
All community-made cases are yellow as opposed to the Valve-made black cases.
The Winter Offensive Weapon Case has a chance of being offered to players with prime status once per week as part of their weekly care package. The odds of receiving a case from the rare case drop pool is 1/100 or 1%.
Alternatively, it can be obtained by trading with other players, or purchasing from the Steam Community Marketplace and some third-party marketplaces.