You can play İmpostor in a99io.com as unblocked.
In the impostor game, which is similar to the Among Us Online game, you have to choose any of the 3 maps you have to do, become an impostor and kill the other players and not get caught. This will not be easy. You can move with W, A, S, D keys and kill players by pressing Kill. If you use the vents very well, your chance of getting caught will decrease.