Deal
Khan didn't remain still in front of that initial success. He shot forward and threw a kick in the spot right behind the source of the suppressed cry.
A grunt followed his action, but he didn't feel anything. Khan couldn't confirm whether he had hit the man, but he still launched another kick aimed at the source of the new sound.
Nothing happened after the kick. The area remained utterly silent, but something eventually reached Khan's senses. A few drops of blood materialized mid-air before falling on the ground.
Khan's thoughts ran quickly as he reviewed his initial guess. The mysterious man clearly had access to something stronger than simple invisibility. It seemed that everything in the spell's range blended with the environment and became impossible to perceive.