What is an unpopular gamemode that you think is overlooked and deserves more players?

You always hear about DarkRP, Prop Hunt, TTT, and all of the other modes that became huge and are largely what gmod is known for, but what is a mode that has a smaller playerbase you enjoy a lot?

One that I've had plenty of fun with friends in was Smash, where you're standing on pillars and floor tiles that have physics applied to them and boulders come falling from the sky to flip them around. Winning means you have to be the last one standing (or the last one who hasn't fallen to their death yet!) There's also a variation where players are selected to shoot the boulders. Both are simple but can be fun for hours with the right crowd. I wish it had more recognition..