Garry's Mod vs Salem
Garry's Mod
Garry's Mod is a sandbox game that brings back the hilarity and joy of being able to simply experiment and have fun. There aren't any objectives in this game; you are simply given the tools you need to play with... just like that time when you get your first Lego set. Being a purely community-driven game, Garry's Mod is quite the multiplayer game. You can hop into any of the created content or game modes and have fun with your friends, except for buy-to-play games in which you'll need to own the base game first. You can also opt to spend time to create new content that you can then share with the community. If you'd rather play in peace, you can play Garry's Mod offline too.Garry's Mod is definitely the sort of game that creative players would enjoy. The amount of stuff you can play there is astounding and of course, you are given absolute freedom to express yourself through your creations if you choose to do so.
Salem
Salem is an old-school and somewhat obscure (but fun) sandbox MMORPG that unlike Wurm Online has a stronger emphasis on its in-depth crafting system and survival aspect rather than building.Similar to Wurm Online though, Salem is not a voxel-based game, but you are still able to mold the game environment through resource gathering, mining and digging in a way that reminds me of the currently-shelved MMORPG, EverQuest Next: Landmark. Of course, although not exactly the focus of the game, you can still build your homestead and the process is quite similar to Wurm Online except that it occurs at a much higher speed.
Not to mention, the game world in Salem is simply humongous to the point where it feels like an actual world. Salem also borrowed some features from ArcheAge where open-world PvP is the norm, so you'll need to be vigilant at all times, but players who kill and steal for no reason will be labelled as criminals and can be punished.
However, as good as it is despite being an indie MMO and all, Salem does have its fair share of flaws due to its low development budget. So, we'd recommend you to take a look at Salem without carrying along any high expectations. It's a pretty good MMORPG like Minecraft, but if you're expecting a Minecraft clone, you may end up disappointing yourself.