Tridrone
From Ardrana
Tridrones are modrons which appear as three-sided pyramids with spidery arms and legs. They typically supervise squads of 12 duodrones, who in turn pass their orders to the monodrones. Tridrones can carry out multiple-task projects on their own. Typically, they receive a general order, which they divide into smaller tasks to be fulfilled by the duodrones.
In the modron army, tridrones serve in special companies, equipped with three javelins per being, which they hurl before entering melee. They are capable of reporting actions and observations and actually planning limited objectives on the battlefield.
Note: Tridrones originally appeared in this form in the Planescape AD&D campaign setting from TSR. Their use here is for the purposes of providing context for the campaign only.