(The Agony spell, as most spells, only target one opponent per casting)
Another 20 minutes goes by before the orc who disappeared into the tunnel sticks its face out the entrance again. It looks around into the darkness and barks softly to itself. The other orc who scouted further down the road softly pads its way up the grassy bank in the distance and flashes something reflective that only those at the tunnel entrance can see. It flashes twice and them after a pause a third time. The orc at the entrance grunts quietly. He mumbles something to himself in the orcish tongue then lightly raps on the tunnel wall twice. Pauses and raps a third time. You can hear it echo down into the depths.
Then the orc by the tunnel entrance mouths some more orcish gibberish and makes a few hand gestures, while removing its stinking furs and places his spear to the side of the road. As you watch its body contorts. It's arms lengthen, bend, and crack in unnatural angles. A black fur developes on its skin and it's torso folds into a ball. When complete a large bat remains in its place. It squeals and takes to the sky.
From within the tunnel the sounds of footfall can we heard. Too many to keep quiet in the tunnels.
An ogre sticks its snout out and lumbers through the exit. Orcs in a line 3 wide begin walking out of the tunnel and down the slope to the road toward town. 12...24...another ogre...36...another ogre pulling a wagon with a barrel on top..another ogre pushing the wagon...48 orcs...60...on an on they trod...120 orcs...another ogre...150...all wearing a mix match or leathers, furs, and mail. Carrying swords, axes, bows, and spears....
Finally the last stragglers exit the tunnel and march toward the town.