Serious New Games to Mod?

I love to play games especially thing like Terraria and then you beat it and Mod it. Skyrim is another great one but these games got old. Somewhat anyway what are new games with big modding communities?

If you love sandbox games, Mount and Blade Warband is a modding classic. The base game itself is incredible but difficult and has a high learning curve, but I promise it's so worth it once you get the hang of the game. Then you get into the mods and they're all like different games. Warband has so many total conversions its not even funny. Highly recommend this game if you have the patience (but if you don't, there's cheats too and the game is still super fun)

Try out Garry's Mod, it's fun and has loads of mods.