Tyson Rios

Tyson Rios is one of the two protagonists in Army of Two, and Army of Two: The 40th Day. Rios is part of SSC's 'Army of Two', and works alongside his partner Elliot Salem to complete dangerous operations. Rios is physically the tallest character who is encountered in the game, and is built like a tank. 
 

Actions

While Salem is more willing to rush enemy positions, Rios prefers to take things slowly and let them play out how he wants them. Salem is more concerned about the money than his own personal safety, and Rios is the polar opposite.
 

Rios during the Ao2 story

 Rios was a soldier alongside Elliot Salem during the war in Somalia. The two men were sent to deal with a warlord in the capital of Mogadishu, and to meet with another soldier. This soldier is one 'Philip Clyde', and was a private contractor. Clyde operates as a lone wolf, and Salem and Rios have to fend for themselves for much of the battle through the streets of the capital. Once the warlord is killed, the group of three are told to regroup for extraction in a Black Hawk helicopter. Once they have boarded the plane, their commander for the mission, Richard Dalton, tells Salem and Rios that they "were like an Army of Two". This is likely where the name 'Army of TWO' came from.
 
Salem and Rios are sent to Afghanistan at the height of the war, tasked with destroying M-11 ballistic missiles. They are also asked to kill a dangerous terrorist as well, to prevent the production of more missile warheads or potentially, chemical warfare. As a backstory, two politicians are fighting back in the US about privatizing the military. One of these politicians is against the idea, and one is encouraging it.
 
The politician against the idea, Richard Whitehorse, argues that PMCs (Private Military Corporations) could simply start war 'for profit'. Salem and Rios are sent to Iraq, to rescue a former squadmate, and to terminate Ali Youssef, another key in the terrorist regime. Their squadmate, Lt. Col. Eisenhower is loaded onto a chopper, to be evacuated from the area. However, the helicopter is almost immediately shot down.  Rios suspects a conspiracy behind Eisenhower's demise, but Salem disregards it and says that he "was in the wrong place at the wrong time". The Army of Two push onwards and eventually kill Youssef.
 
After an unspecified mission, Rios and Salem are told to save a US aircraft carrier that had been hijacked by a Filipino terrorist group. During this mission, Rios and Salem find Clyde doing dealings with the terrorists. Rios sends the information for analysis, and they discover Clyde has been selling positions to the enemies.
 
Upon completion of this mission, Rios and Salem are sent to assassinate a Chinese terrorist, and unwittingly kill the senator, Richard Whitehorse. They have to flee along the Li-Jiang river to escape the Chinese forces. At the end of the game, you are tasked with killing the men who sold out the positions of troops: SSC.

Trivia

• In the Army of Two graphic novel, Dirty Money, we learn that Rios has a girlfriend who he cares deeply for.
• During the graphic novel it is also mentioned that the damage caused to Rios face (major scarring) was sustained during a terrible accident, and Rios never lets his guard down after this.