Helm! Helm!
The Treason of Saruman #12 (x3)

Play only after the resolving enemy attacks step is complete.

Combat Action: Exhaust and discard a Rohan ally you control to choose and discard a non-unique enemy engaged with you.

"Helm is arisen and comes back to war. Helm for Théoden King!" –Riders of Rohan, The Two Towers