The great, great grandson of Rambo, Rambo IV: Pearl of the Cobra (I won’t even touch that) has added broken armed Army Ranger and evil doctor/orchid-loving Anaconda bait Matthew Marsden to its ranks.
Matthew hops in the boots of a mercenary who joins forces with the "save them missionaries!" Christian warrior previously known as Rambo, the VC/Russian blower-upper. A previous script (there’s been many) had Rambo teaming up with a guy on the lam from the US government– sounds like Mr. Mercenary may be some kind of variation on the theme.
As you know, Rambo IV is filming in Thailand and will hopefully feature Rambo killing upwards of 60 men and countless trees with a single machine gun.