How can I use a command block to turn everyone (except myself) into adventure mode (gamemode 2)? Any command which does this would be awesome.
/gamemode adventure @a[name=!<player>]
What this exactly does is:
/gamemode adventure - Sets gamemode to adventure.
@a[name=!<player>] - Targets all players, except the name of the player specified there. The
! means "except".
If your Minecraft name for example was MrLuca, then the command would be:
/gamemode adventure @a[name=!MrLuca]