Reach Rank Ten in Multiplayer mode to unlock the Kolibri for purchase for 150 warbonds. The Kolibri is a pocket-sized gun held between the thumb and index finger. It fires 2mm bullets, and was (at one point) available commercially to the public. The magazine holds 8 rounds. The gun is so small, it cannot be held in the palm of your hand. Instead, you have to pinch the pistol's grip between the forefinger and thumb to get a grip. There really is no other gun quite like it. The 2mm bullets barely inflict any damage to your opponents, but you can still earn kills with it. It is more used as a novelty taunt, as nobody wants to get killed by the tiniest gun in history.