Black Forest (first version)
Up to 20 families would struggle to survive against nightly monster attacks. The nasty element was that both cooperation and betrayl were viable strategies, and at certain points you would re-evaluate. Maybe you did well with cooperating so far, but now... today (each turn was one day) it would benefit you so much to betray your neighbour and throw him under the bus - or monsters, as it were.
The game was fun, challenging, reached all the development goals I had. It was simple in graphics, but the gameplay was great. Sadly, it rarely managed to fill a game up with 20 players. And after a few dozen games were played, people became tired of waiting for days for a game to fill up. Theoretically that was never a problem because it was a play-by-mail style turn mechanic where you would make your turn, send it to the server, and get an update when everyone had done it. So you would log in once a day, make your turn and be done. But that slow gameplay, coupled with the long waiting for a game to start was problematic and the playerbase dropped below viable levels.
So I abandoned the game...
...until it's revival in 2021 - see Black Forest