[Johnny got his gun]

Where I come from, if you cut the wall repeteadly with your knife it means you're challenging your last opponent to a knife duel. ;-)

I decided to automate this process.

If only you and another person on the opposite team remain in the round, you can hit a wall (or another object) with your knife, THREE TIMES in fast succession.
By this action you challenge your opponent to a knife duel. The person you challenge gets a menu where he can accept/decline your
challenge. The challenged person has 10 seconds to decide his mind, else the challenge is automatically declined, and the menu should be closed automatically.

Should a knife duel start, it works out pretty much like a round of Knife Arena: you can only use the knife (and the C4!).
As soon as the round ends the Knife Arena mode is turned off.