The present invention relates to a system (1) of remotely controlled drones (10, 12) fitted with respective cameras (14) enabling a virtual shot from an assailant drone (12) at a target drone (10) to be validated by recognizing the target drone (10) in a video image (17) supplied by the camera (14) of the assailant drone (12) while firing a virtual shot. The recognition means comprise a beacon (15, 16) arranged on the target drone (10) and covered in two first strips (18) of a first color reflecting light at a first wavelength lying in the range 590 nm to 745 nm, situated on either side of at least one second strip (19, 20) of a second color reflecting light at a second wavelength, lying in a range 445 nm to 565 nm. It is thus possible to identify very reliably drones flying in an open space whether outdoors or indoors, in spite of the very great variety of interfering details present in the background images that are likely to be picked up by the camera.