Among Us is a very simplistic video game version of mafia. In Among Us, you play as a crewmember on board a spaceship. During the "day phase", you run around doing your assigned tasks - ie, minigames like connecting wires together, or memorizing a passcode and inputting it, etc. The scum players who are randomly picked walk around the spaceship trying to murder the other crewmembers. If a town crewmember stumbles upon and reports a dead body, the game comes to a halt and the playerbase enters a voting phase, where the players can talk to each other for 2 minutes and decide if they want to lynch someone (by ejecting them out the airlock). However, unlike forum mafia games, where the debators can thoroughly break down their evidence and arguements, the voting phase in Among Us is... very careless. With 2 minutes, there isn't really any time for people to thoroughly explain their position, so it usually winds up being one guy points a finger at another guy and everyone else bandwagons out of self preservation and that's that.
You can buy Among Us for $5 on Steam. It's quite fun to play with friends, but it wears out its welcome after a few hours. If you liked the idea of Among Us but want a more indepth game, get Town of Salem, or join a forum mafia group.