The MancJS code golf server is pretty good, but requires uploading a file instead of editing it in the browser.
You will need to write extra challenges as the built-in ones aren't very good.
CovHack has a dockerised fork here for easy deployment.
Werewolf, sometimes referred to as Mafia, is a party game like the game "Town of Salem". Roles and rules can be found here but is effectively a race to find who the werewolf is before all the villagers get killed.
Code in the Dark
Basically, recreate a website without out previewing your code.
Under MLH events this goes as
@baahorn forked MLHs service for CovHack and removed MLH branding (a licence requirement) and the dependency on MyMLH.
Otherwise, you can use the editor here and use a google drive folder for uploads.
HackNotts in particular has had success inviting university societies such as the Video and Board Game Societies to run mini events or games corner.