Become the Musician
This game is going to challenge not only the singer in you, but also the actor. As the title suggests, the point of the game is to turn into the musician whose song you're performing. Everybody should pick a song they know very well and by musicians they will know how to mimic. Alternatively, you can choose songs for each other and just wing it with impressions. Ask the audience at the bar to decide who did the best impersonation.
Fade Out
The point of karaoke is to sing the song at least somewhat on key and correctly, which is made easier by lyrics being displayed on screens in front of the singers. Wait for the singer to start singing and then fade out the lyrics and let them fly solo. Fade in after a while to see if the singer is still in sync with the song. You can do the same with the melody.
Own the Song
The point of this game is to make up your own words to the song. The singer should pick an unfamilliar song. Until the first chours, they can have the lyrics on but after that, you shut the lyrics off and the singer should make up h;r own lyrics. Once again, it is up to the audience to decide who came up with the most clever words.
Involve the Crowd
This is the game in which you and your friends will test your show-making skills. The object of the game is to get the audience involved to the maximum possible level. Get on stage, pick an upbeat song and try to engage the crowd by encouraging them to sing along or to copy your dance moves. The winner is the singer who gets the most response from the people in the audience.