Complete the indicated task to unlock the corresponding weapon for purchase. Note: They cannot be customized.
AMR (sniper rifle): Find 20 relics.
Bull (shotgun): Find 10 relics.
Bushman (assault rifle): Activate all radio towers.
Japanese Tanto (replaces melee weapon): Find six Letters of the Lost.
Ripper (light machine gun): Survive six Trials of the Rakyat.
Shadow (pistol): Take over 17 encampments.
Shredder (sub-machine gun): Collect ten memory cards.
Search the indicated locations to find the corresponding animal.
One Horn Buffalo: Camp Murder outpost, Path of the Hunter.
Undying Bear: Cradle Gas outpost, Path of the Hunter.
Black Panther: Outpost southeast of the mansion, Path of the Hunter.
Golden Tiger: Mosquito Yard outpost, Path of the Hunter.
White Belly Tapir: Rust Yard outpost, Path of the Hunter.
Blood Komodo: Cliffside Overlook outpost, Path of the Hunter.
Yellow Neck Cassowary: AM-12 outpost, Path of the Hunter.
Maneater Shark: Kell's Boat Repairs, Path of the hunter.
Travel to the indicated location to find the corresponding feature.
Big cave: X:331.8, Y:458.1
Boat color cycle: X:641.5, Y:408.2 (travel here by boat; also does it on the ocean bottom)
Dead body cave: X:630.2, Y:685.0
Easy "Fearless Or Stupid" achievement or trophy dive: X:752.7, Y:656.1
Flying Fish: X:756.3, Y:634.3 (travel here by boat)
Goldilocks and the Three Bears reference: X:796, Y:647 (three chests with bear claw marks)
"Hi To The Internet" achievement or trophy: X:620 Y:557 (interact with buried head; it resembles the front box artwork)
Inside the rocks: X:721.2, Y:747.0 (travel here by jet ski from town and ride into the crevice at this location)
Invisible Water: X:588.8, Y:781.1 (walk near the nearby cliff and you will be suddenly underwater)
Moray eels: X:814.7, Y:612.0 (search near the bottom; they will wrap around you)
Ocean dry patch: X:302.8, Y:285.6 (travel here by boat, fall to the ocean bottom and walk around; try pushing the boat)
Outside flashlight: X:706.5, Y:643.5
Rock slides: X:702.2, Y:783.4 and X:465.6, Y:665.8 (jump in the rock crevices at these locations and slide upwards)
Table goat: X:360.4, Y:740.7
Treasure hole: X:346.9, Y:700.5
Underwater toilet and sick soldier: X:807, Y:637 (Video)
Vultures: X:377, Y:793
Walk through wall in "Mother Lode" mission: X:684.3, Y:731.3 (enter mineshaft and jump across to the piece of wood on the right wall; walk through the wall here)
Waterfall glitch: X:678.1, Y:635.7 (behind the waterfall, jump through the back wall; Cargo Dump mission location)
X-ray glitch: X:761.7, Y:752.1 (in the Badtown store, jump on the counter and on the lantern and jump across to the shelf; stand up and look around for a weird view)
Easy outpost liberation
Use the following trick to liberate an outpost without being detected. When you find an outpost that has a caged animal (for example, a bear or tiger), find a good hiding location inside the outpost that has a good view of the cage but far from it. Select any weapon with a sound suppressor and shoot at the cage. Make sure no guards are close to you when you shoot. Eventually the door to the cage will break and the animal inside will be freed. All the guards and guard dogs will turn their attention to that animal. The freed animal will proceed to "liberate" the outpost for you. All you have to do is remain hidden until it is over. Doing this twice will allow you to to unlock the Ninja Step skill, which makes you very silent. It is best to scan the entire area with your camera beforehand so you can see the progress of the animal when you free it. It also makes for a great show.
Crocodiles are almost always hiding in the groups of lotus flowers in the rivers and waterways. They will not move unless you get too close. Note: If you use the Recurve Bow, it will kill them in one shot.
Hidden video sequences
Every time you travel to the grotto underneath the mansion, take one of the "eat me" berries for hidden video scenes.
On any of the highest mountains, take out your camera and zoom in. Glance around the land and you will see many bright lights. These are your objectives lighting up.
Land on power lines while using the wingsuit to do super bounces.
Shoot the crabs on land for a gory mess.
Some of the trees are flexible if you shoot them.
Complete the following achievements to unlock Xbox Live Gamerscore points.
Free Fall (5 points): Freefall more than 100m and live (Single Player only).
Inked Up (5 points): Earn 5 skill tattoos.
Fully Inked (30 points): Earn every tattoo by learning all the skills.
Money to Burn (15 points): Spend $5000 at the shop.
Aftermarket Junkie (20 points): Buy all attachments and paint jobs for one weapon. (Video)
Rebel With a Cause (10 points): Liberate 3 outposts. (Video)
Island Liberator (40 points): Liberate all outposts. (Video)
Unheard (20 points): Liberate an outpost without triggering an alarm. (Video)
Full Bars (20 points): Activate 9 radio towers.
Archeology 101 (20 points): Gather a total of 60 relics.
Dead Letters (20 points): Gather all "Letters of the Lost".
Memory to Spare (20 points): Gather all the memory cards.
Jungle Journal (20 points): Unlock 50 entries in the Survivor Guide.
Bagged and Tagged (10 points): Complete a Path of the Hunter quest.
Road Trip (10 points): Complete a Supply Drop quest.
In Cold Blood (10 points): Complete a WANTED Dead quest.
Let the Trials Begin (10 points): Beat any Trial of the Rakyat score.
Poker Bully (20 points): Win $1500 playing poker.
Hunter Hunted (10 points): Lure and kill a predator.
Poacher (20 points): Hunt and skin a rare animal.
Artsy Craftsy (10 points): Craft 5 upgrades for your equipment.
Needle Exchange (15 points): Craft 25 syringes.
The Good Stuff (15 points): Craft a special syringe.
Say Hi to the Internet (10 points): Find the lost Hollywood star. (Video)
Heartless Pyro (10 points): Kill 50 enemies with the flamethrower (Single Player only). (Video)
Love the Boom (10 points): Kill 4 enemies simultaneously with one explosion (Single Player only). (Video)
Rock Always Wins (10 points): Fully distract 25 enemies with rocks (Single Player only).
Island Paparazzi (15 points): Tag 25 enemies using the camera (Single Player only).
Fearless or Stupid (15 points): Dive more than 60m (Single Player only). (Video)
Never Saw it Coming (20 points): Kill an enemy with a takedown from above from a glider, zipline or parachute (Single Player only). (Video)
Improper Use (5 points): Kill an enemy with the Repair Tool (Single Player only). (Video)
Toxophilite (10 points): Kill a target from 70m or more with the bow (Single Player only). (Video)
Here We Come (20 points): Complete "Ready or Not" Co-op map (Online/Offline).
Return to Sender (20 points): Complete "Sidetracked" Co-op map (Online/Offline).
Rocking the Boat (20 points): Complete "Overboard" Co-op map (Online/Offline).
Hide and Seek (20 points): Complete "Lights Out" Co-op map (Online/Offline).
Late Night Pick-up (20 points): Complete "Rush Hour" Co-op map (Online/Offline).
Getting Even (20 points): Complete "Payback" Co-op map (Online/Offline).
Additionally there are twelve secret achievements
First Blood (10 points): Escape the pirates and survive in the wilderness.
Magic Mushroom (20 points): Return to the doctor with the cave mushrooms.
Worst Date Ever (20 points): Rescue Liza from the burning building.
One of Us (20 points): Complete the Rakyat initiation.
Hands Off My Stoner (20 points): Rescue Oliver from the pirates.
Retake Wallstreet (20 points): Rescue Keith from Buck.
Have I Told You? (50 points): Survive the encounter with Vaas and escape.
Taken for Granted (50 points): Kill Vaas.
Higher Than a Kite (20 points): Use your wingsuit to reach the Southern island.
Deep Cover (20 points): Complete Riley's interrogation.
Poker Night (50 points): Kill Hoyt.
What a Trip (100 points): Attend the final ceremony.