Trench

How Trench joined the Tourney
For reasons unknown, Trench Mauser and Barney Ross parted ways after collaborating as partners for many years. Trench Mauser went on to form a rival group of mercenaries, though his unparalleled skill sets allow him to take on deadly operations alone.

Many years later, Trench Mauser is contacted by Mr. Church along with Ross himself about a mission to Vilena to assassinate rogue CIA officer James Munroe (though they believe they will be targeting General Garza). Trench Mauser playfully teases Barney Ross throughout the entire meeting until claiming to be busy and suggests that Mr. Church give the job to Barney Ross before leaving.

Trench Mauser is rescued along with the billionare doctor by the Expendables and in turn owes a debt to Barney Ross. After being rescued, Trench Mauser leaves to reunite with his own team.

Trench Mauser rescues the Expendables while they are trapped in a cave (paying his debt to Barney Ross). After rescuing them, he and Mr. Church join the Expendables in their battle against Jean Vilain. Killing hordes of Sangs alongside Mr. Church, he also fights alongside Booker. After the battle, he says goodbye to Barney Ross and leaves with Mr. Church, Booker and Maggie.

Trench Mauser played a major role in The Expendables 3. He showed concern for Hale Caesar in the hospital. Afterwards, he and Barney Ross carried out the Conrad Stonebanks mission in Romania, staying behind to guard the landing site. He was also afraid that Conrad Stonebanks would come after him, so he hid until the final confrontation with Conrad Stonebanks. He went with Yin Yang and Max Drummer to the battle scene, where they came to the aid of the Expendables that were trapped in an old abandoned building that was about to be demolished by C4 explosives that had been set up by Conrad Stonebanks. Eventually, the mission succeeded and Conrad Stonebanks was killed. He and the other Expendables celebrated at the bar, waiting for the next mission.

How to unlock
For both methods, you must fight Trench at the Albanian Airport. Alternatively, you can avoid clashing with him by wishing for him from Shenron, or purchasing him for 600 Smash coins in the Smash Store. After defeating Trench, wishing for him from Shenron, or purchasing him from the Smash Store, the announcer will say "Someone else has joined the Tourney!" after a Smash Ball appears on the lower-right corner of the screen with a message saying "You can now use Barney Ross's old teammate turned rival, Trent "Trench" Mauser!" He will be seen left of Miara, right of Giran and below Eraserhead.
 * Clear Man the Meat level 4 with Sinestro.
 * Play 3195 matches.

When highlighted
Trench smokes a cigar.

After the announcer calls his name
Trench does a lariat and shoots an AA-12 shotgun as the camera zooms saying "What are you gonna do?"

AA-12 (Neutral)
Trench shoots an AA-12 shotgun at the opponent.

Beer Kick (Side)
Trench moves forward doing two hard kicks.

Backing Up (Up)
Trench does a jumping somersault kick, then shoots a Walther P38 downward.

Fireman's Takedown (Down)
Trench grabs his opponent's, puts him/her in a fireman's carry, then punches his/her face and drops backward.

M240G Machine Gun (Hyper Smash)
Trench readies an M240G Machine Gun then fires it in multiple directions in front of him for 10 seconds.

I'm Going Back (Final Smash)
Trench does a double hammer punch. If he hits, he does three punches with one fracturing the skull, then shotgun butts the opponent's leg and chest, hitting the ribs, then aims the shotgun at the opponent's face and says "I'm back!" then shoots him/her hard enough to blow him/her away.

Victory Animations

 * 1) Trench flicks his cigar away saying "Short notice." then cocks his AA-12.
 * 2) Trench does two swinging punches saying "I'm getting out of this business, and so should you."
 * 3) Trench cracks his knuckles and swings his left hand saying "Then I guess our favors are done."

On-Screen Appearance
Trench jumps out of a helicopter saying "I'm back!"

Trivia

 * Trench's rival is a former Green Lantern Corps member who had turned to forming the Sinestro Corps and Hal Jordan's arch-nemesis, Sinestro.
 * Trent "Trench" Mauser shares his English voice actor with Conan, John Matrix, the Terminator and Carl Hauser a.k.a. Douglas Quaid.
 * Trent "Trench" Mauser shares his Japanese voice actor with Conan, Tiki Tong, Carl Hauser a.k.a. Douglas Quaid, Toguro, Batman, Tree Rex, Dozle Zabi (in all his Mobile suits), Tigger, Taurus Aldebaran, John Matrix, Tony James, Gen. Maj. Karl Ludwig, Rambi the Rhinoceros, Terminator, Mr. Chicken, Kingdra, Mr. Gomez Addams, Leodore Lionheart, Godzilla, Foghorn Leghorn, Gale Raregroove, Junior Gorg, Janemba, Mace Windu, Soldier Stonekong, Ride Boarski and Bojack.
 * Trent "Trench" Mauser shares his French voice actor with Jafar, General Javier Diego and General Stuart Adams.
 * Trent "Trench" Mauser shares his German voice actor with Col. Podovsky, Barney Ross, Conan and Douglas Quaid a.k.a. Carl Hauser and General Javier Diego.
 * Trent "Trench" Mauser shares his Mandarin Chinese voice actor with Mighty Eagle.