Commanding a unit makes it move in the specified direction immediately. Just like at the start of their owner's turn, the unit will attack enemies if it moves into them and won't move if it is blocked by a friendly unit or structure.
Commanding confused units will cause confusion to apply, allowing the unit to randomly move sideways and attack friendly units and structures.
Visually, command is represented with a horn and blue concentric circles.
Command is very versatile and powerful. It can surprise your opponent and win the game sometimes, but used poorly it can make your units vulnerable.
Command friendly units into the enemy base for instant damage.
Move friendly units closer to the enemy base and gain frontline.
Force a friendly unit to move out of the way to free up a tile.