Level 19: Dam
Go to the Volcano Laboratory
Again, CryTek is blameless in the matter of the inclusion of a level in which the hero of the game is stripped of all of his hard-earned weaponry and set to defend himself with nary but his wits and a sharp stick. This level archetype is legislated into the FPS genre; its a matter of jurisprudence.
Give them credit for sticking it to the man, though: Jack actually gets a token M4 to begin the level. It has all of ten rounds in it, though, rendering it decent for killing the Tridgen near your starting point and not much else. (Cool part: if you kill the Tridgen in the middle of the stream, the waters flow will pick up the body and send it over the nearby waterfall.) With any luck, you may have two or three bullets remaining to you after your fight, but it wont matter much; three bullets isnt going to put a dent into the forces of the mutants lying in wait at the bottom of the waterfall. Well, maybe itll dent them, but all thatll accomplish is alerting them to your presence and speeding up your death.
The trick here, if it can indeed be called a trick, is to just run like hell and hope you dont attract the attention of any Tridgens on the way. There are plenty of Fat Boys in the area, but theyre of the unarmed variety, thus making them not a danger. There are a few armed mutants and Tridgens in the area, though, and if any of these guys spot you, youre probably dead.
Before you go off the waterfall, take a moment and note the position of the downed helicopter near the waters edge below. This is your first goal; inside of it are two miniguns, a suit of armor, and a clip for your M4. Getting there is the hard part, of course, and youll likely need a few tries before you can make the journey and actually survive. Your best bet is to jump off of the waterfall before you attract the attention of any of the mutants below; they can see you from down there, and will swarm around the pool at the bottom of the falls if your stealth meter hits the red.
After you hit the pools, try to swim along the bottom of the river for a bit before standing up and running to the right. Stick close to the right side of the river here; the deeper sections of the forest are where the Tridgens await. If you spot any mutants with guns, though, you should obviously attempt to avoid making contact with them. Try to save your sprinting juice by only running when a real threat is on your tail; the Fat Boys shouldnt be able to catch up with you after you put a bit of distance between yourself and them. If you can avoid any other mutants, you should be able to get to the helicopter in one piece.
Once there, a short cutscene ensues before you get to unload the miniguns on the mutants. Aim at the mutants on the northeast side of the chopper first; the baddies across the water are the ones with the guns, so take down anyone whos armed before moving on to the Fat Boys. If you spot a Fat Boy with a rocket launcher, make him your priority, even if hes firing at the fortifications up the hill; hell eventually start firing at you, and the tight quarters make dodging rockets a risky proposition. Dont neglect the southwestern side of the equation, though; there are still plenty of mutants in the jungle, and any of them that are nearby will be attracted by all the gunfire. If youre having trouble spotting targets, get out of the minigun and use your M4s zoom feature. It isnt fantastic, but should work.
When youre ready to head up the hill, grab one of the AG36s from the Locusts on the beach and check to make sure that its fully loaded. By the time you reach the top of the hill, the fighting between the Fat Boys and the mercenaries here shouldve ended, which probably means that youll have anywhere from one to four Fat Boys to worry about, and perhaps another Locust. Youre still underpowered, and probably dont have much ammo, so do your best to dodge the Fat Boys rockets, dash through the hole in the gate, and take the stairwell to your right, picking up the rocket launcher on the way. The Fat Boys will likely follow you up the stairs, so pick the second minigun here, the one further from the stairwell, and start getting your headshots. Depending on your difficulty level, the FBs rockets will likely be off-target at this range, but youll be close enough to get headshots consistently.