FNF Imposter V4 appears to be a mod or a fan-made version of the popular rhythm-based game Friday Night Funkin'. In the Friday Night Funkin' game, players engage in musical battles against various characters by hitting the correct arrow keys in time with the music. The goal is to impress your opponent and win their approval.
It seems that FNF Imposter V4 is a specific modification or iteration of the game, possibly featuring characters or content inspired by the popular online game Among Us, where players work together to complete tasks on a spaceship while trying to identify the impostors among them.
The "Friday Night Funkin' game has gained immense popularity due to its catchy music, engaging gameplay, and the ability for players to create their own custom content or mods. "FNF Imposter V4" is likely one such mod that introduces new characters or music tracks to the game.