A Pheromone is a feature on antwar.io that allows for the marking of a trail on the surface. An ant secretes these automatically when handling any kind of food outside the nest. Everyone can see these markings, including members of an opposite colony.
The pheromone color changes according to the team that the queen belonged to when the egg was laid. Members stolen from opposing broods will keep their old team's pheromones, despite being controlled by a different colony.