FORT HUNTER-LIGGETT, California -- Flanked by Californian hills and sun burnt grass, Army Reserve Soldiers had a problem. They were manning an entry control point to a base as part of Warrior Exercise 2014, when a band of California National Guardsman launched an attack on their position.

Simulated casualties littered the control point. Wounded attackers called for help, while others pretended to mourn the fallen. Two Soldiers from the Reserve unit, public affairs broadcasters by trade, stood frozen in the middle.

"There is no right or wrong decision. The only wrong decision is not making one," said Staff Sgt. Kevin Ward, an observer-coach/trainer with the 189th Infantry Brigade, First Army Division West.

The Warrior Exercise, held this year during July, serves as an annual culminating training event for combat support units throughout the Army.

Though the majority of the more than 40 units training are from the Army Reserve, the 14-day exercise also tests and strengthens the interoperability of Soldiers from the active duty, Reserve and National Guard components, collectively known as the Army Total Force.

"They're weaving in much like they would do on the modern battlefield. We don't necessarily ask what component somebody is. We just notice it says 'U.S. Army' on their uniform," said Col. Randall Wickman, commander for 189th Infantry Brigade, garrisoned at Joint Base Lewis-McChord, Washington. "We have to train like that so it is less impact and less startling to the system when we do it in combat."

The 189th itself is comprised of active and Reserve battalions, which Wickman said uniquely equips them to be the primary trainers during the multi-component and multi-echelon event.

The active duty and Reserve partnership starts at the highest level of the exercise -- the expeditionary sustainment command. Soldiers with 364th Expeditionary Sustainment Command, a Reserve unit out of Marysville, Washington, partnered with the 593rd Expeditionary Sustainment Command from Joint Base Lewis-McChord.

The two units, usually charged with coordinating support and logistics for thousands of Soldiers, will transfer responsibility of those tasks during the exercise just as they would while deployed.

Below the expeditionary sustainment command, observer-coach/trainers, known as O-C/Ts, shadow units during both phases of Warrior Exercise: mission rehearsal and a simulated mission in an adaptive training environment.

The O-C/Ts, like Ward at the entry control point, are predominately from the 189th Infantry Brigade and have backgrounds in combat occupations, like infantry and armor. They walk step-by-step through warrior tasks with the support units during the mission rehearsal phase.

Ward, a cavalry scout, said he keeps in mind that support Soldiers are often attached to combat units and could be attached to his in the future.

All Soldiers, regardless of their occupation, are expected to know basic warrior tasks that range from convoy operations to room clearing. Most begin the exercise prepared to start with the basics.

"They're not coming in here with the preconceived notion that they know everything, so they're more open to learn the actual doctrine and the fundamentals of something and then put it into practical application," Ward said.

In addition to refreshing individual skills, Warrior Exercise as an annual training event allows units to test their abilities to work as teams in a simulated combat zone.

For Reserve 1st Lt. R.J. Salavec, commander of 409th Engineer Company out of Fort Collins, Colorado, the exercise was his third annual training event with the two prior being construction and humanitarian aid missions.

"We try to do something four or five times a year to get out into the community and build something, but nothing as tactical as this, nothing this far out of Fort Collins," he said.

Company-level units like Salavec's can train in their occupations at their home stations, whether that be building a bridge like the 409th Engineer Company or taking photos and video like the reserve public affairs Soldiers defending the entry control point.

"We're trying to stress the importance to these guys of making a decision," Ward said.

Warrior Exercise puts those Soldiers in situations they won't find during a weekend drill but may encounter on the battlefield, where decisions can be the difference between success and failure.