The 22nd Shock Troops Battalion (map designate: ODST || 22) was a shock infantry formation of the UNSC Marine Corps during the Human-Covenant war. This shock troops battalion was garrisoned in the northern Viery territory of the Human colony of Reach. It participated during the invasion to counter Covenant Army landing forces. The Bullfrogs, a specialized unit which implemented the use of jetpacks, were deployed during the battle in New Alexandria, aiding SPARTAN-B312 in destroying Covenant occupation forces.