Both Serious Sam 3 and Red Orchestra 2: Heroes of Stalingrad now have Steam Workshop support, meaning that players can now use community-made weapons, maps and mod the games.
In the case of Red Orchestra 2, Tripwire Interactive announced today that while there isn't much available in the workshop yet, players can expect to play new maps created by modders or get involved in the modding themselves. Tripwire is hosting a "Counterattack" Custom Map Making Competition with $35,000 worth of prizes to be won and a custom PC for the Grand Prize winner.
The Red Orchestra 2 SDK is free to anyone who already owns a copy of the game.
The Serious Sam 3 Steam Workshop support gives players the option to subscribe to modders that use the Serious Editor and there will be more than 60 mods to play with in the Steam Workshop update.