Dex is a member of the Strike Force introduced in SFH2, until he goes rogue during Campaign Mission 8 in the second game. Because of the cloning of the heroes, even though his original died, his own clone is an available unique hero in Strike Force Heroes 3.

Dex's default appearance in SFH3
He is a Mercenary, and specializes in machine guns and explosives in both games.
One of his clones from the previous games fights alongside you in Strike Force Heroes 3.
Appearance
In Strike Force Heroes 2, Dex wears The Lion Helmet and the Rambo Body. He uses the Desert Storm camo.
In the third game, he always wears the same hat and Rambo body unlike other Mercenaries.
He has a very gruff voice with a heavy American accent.
Equipment
In Strike Force Heroes 2, Dex's primary weapon is an LSW Machine Gun with a Grip attachment. His secondary weapon is a First Blood knife. His Killstreak is Surge.
In Strike Force Heroes 3, Dex will be equipped with the default SMAWG and Knife, but his equipment can be customized at the player's discretion. He has the Explosive Temper trait, Disliked flaw, and Ghost Weapon killstreak.
Plot
Dex is a strong, venerable veteran of the second strike force team. Providing either blinding return fire with his machines guns, or combustive carnage with his explosives to turn the tables in battle. Despite his useful traits, Dex has only served for so long because of his paycheck.
After West recieved a call from Iagi about the completed serum for the zombieism that Globex has created, Dex kills West with a bullet to the head before Iagi can give details to rendezvous. In the ensuing match that followed, Dex revealed that GlobeX lines his pockets more, and West's death was just to maintain His bottom line. After the brief match against his former squad, he escapes the base and moves in to kills Iagi as well.
With his head start and the logistic advantage of being lone wolf, Dex gets to Iagi's lab first and the heroes find him dead on the floor when they arrive. Greeted by Dex, he calls in a few GlobeX clones, and you face off with him once again.
One mission later, you face Dex alone in the factory after your team was captured. During the less-than-nostalgic reunion, Dex states that "..I've always liked you, but it's time for you to get crushed!", before getting crushed himself by the GlobeX leader's mech. He unsolemnly tells the player that Dex was too expensive to maintain, thus his death would cut upkeep costs. Dex's dismembered remains are the last we see of him in this game.
Strike Force Heroes 3
A cloned Dex returns to your team after completing Rocket Race 4.0 on insane. While this Dex appears to keep his loyalties amidst dire circumstances, it's safe to assume any attempt of betrayal will be swiftly dealt with.
Trivia
- He is a "lone wolf", according to the Mercenary's biography in a Development post made by Sky9.
- Dex looks like John Price from Call of duty Modern warfare.
- There is good reasoning to this. He looks like John Price in latter installments, has the same battle boonie, and has a similar beard.
- However, as said by Mike, he is not inspired by John Price at all.
- There is good reasoning to this. He looks like John Price in latter installments, has the same battle boonie, and has a similar beard.