Cliché Storm: The film series quite deliberately uses every single trope common in the kind of hyper-violent '80s action films where Stallone made his career.
Complete Monster: Rogue CIA agent James Munroe is a drug smuggler and mercenary who is responsible for his partner, General Garza, transforming the island of Vilena into a Police State, using the people as labor in their drug operation. During his first scene, Munroe kills one prisoner, then derides Garza for his lack of spine, forcing the latter to murder a second prisoner in order to save face. When the Expendables raid Vilena, Munroe captures Garza's daughter, Sandra, who opposes her father's government, and has her waterboarded over Garza's objections. He contracts former Expendable, Gunnar Jensen, to kill the rest of the team, and when Garza turns on him following the Expendables' assault on Vilena, he shoots the general In the Back, kills the rest of his security detail, and tries to make good his escape, though not before instructing Paine and The Brit to torture Barney Ross, and taking Sandra hostage to use as a Human Shield. Caring only for his profits, Munroe is willing to wreck a country in order to increase them.
In 2009, a year before the film's release, Mickie Rourke had an appearance in WWE thanks to his success with The Wrestler in order to work a storyline with Chris Jericho. As at first Rourke didn't trust the company, he brought with him an entourage of tough guys, including MMA fighter Frank Shamrock, boxer Clint Coronel and an Israeli bounty hunter, just in case he got double crossed or something. Naturally, after the film came out and this was made public, a fan in this page was quick to point out that Rourke had assembled his own real team of Expendables.
Talking about WWE, it has adopted Diamond Eyes as one of their themes. From a film that featured a classically trained wrestler (who also trained professional wrestling, actually) kicking a pro wrestler into a fire.
According to Barney, Arnold Schwarzenegger's character, Trench, wanted to be the President. In the 2007 film The Simpsons Movie, there is a President Arnold Schwarzenegger.
Also the close-up of Ross stabbing one of the mooks who were going to rape Sandra. Doubles as Special Effects Failure as the blood looks rather off in the shot and his knife kinda wobbles around unnaturally.
Gunnar's taunt towards Yin Yang is pretty cheesy: "What are you, size two? Bring it, Happy Feet!"
The CGI blood, which led to a lot of mockery from detractors and even some of the film's fans.
The guard that Ross decapitated somehow managed to grow his head back between shots.
The flames covering Paine when Toll Road sets him on fire are obviously CGI.
In many of the scenes involving mooks getting killed by the team it's painfully obvious that the blood is CGI.
They Wasted a Perfectly Good Character: General Garza's twin bodyguards. What's the use of having two star MMA fighters like Antonio Rodrigo and Antonio Rogerio Nogueira in a film filled with many other fighters and martial arts experts if you don't work any hand-to-hand fight scene with them?
Took the Bad Film Seriously: Many critics who didn't like the movie were nevertheless impressed by Mickey Rourke's performance and wondered what such a dedicated performance was doing in a "brain-dead action flick". Oddly enough, a lot of critics, in a doubly inverted version of this trope, were expecting slam-bang action all the way through, but complained about the overuse of CGI (which was not a staple in 80s movies), the too-modern Shaky Cam, and, most unexpectedly, it having too much plot.