Pretty sure this one was on Netflix and it might be still.
Unlike the original Monsters, which dealt with immigration under the guise of giant monsters invading the earth, the sequel is pretty much a straight up war movie with a few monsters thrown in. Four friends from Detroit end up in the same army unit and are led by the gung-ho Frater. On their first mission, they go up against a monster but the bulk of the movie is about a search and rescue operation going horribly wrong. The monsters are popping up in sovereign nations that don't take kindly to US military forces coming in and occupying their lands. So, the army must deal with insurgents and monsters at the same time. The search and rescue goes wrong when the team hits a hidden roadside bomb and are ambushed by insurgents. Killed off one by one, the team has to figure out how to survive and complete the mission. Meanwhile, you know, monsters are tearing around killing people.
I was taken aback by how much of a straight war movie this is. If it weren't for the occasional reminders of the monsters, it would just be a straight war movie. This is one of those that argues for the futility of armed conflict by having a very nihilistic viewpoint of the action. Things get very grim and repeatedly so. By the end, it felt a little like I was getting lectured to by the monster movie, which isn't a great feeling. However, I must say I stay engaged for most of the action and was invested in the characters.
If you don't mind a war movie disguised as horror and you don't mind it being a little preachy, check it out. It has almost no relation to the first movie so you don't need to see Monsters first.