Complete mission walkthrough:
Start off by watching a short cut-scene and listening to what Jack has to say. You'll end up standing on a beach and playing as Will (#1). I guess I won't have to remind you to destroy all of the surrounding crates. Most of them will contain gold pouches. Some of the crates are hidden to the left of a small boat. Enter the jungle and destroy two crates (#1), however DON'T go any further, because you wouldn't be able to return for one of the pendants. Instead, return to the beach. If you would decide to try your luck in the jungle, you would have to deal with several traps and you would encounter quicksand.
Head on to your right. I would recommend that you start off by destroying all nearby crates, including the lower ones. One of the crates will contain your first pendant (#1). As for the rest, you will collect additional gold. Now you will be able to use the ladder (#2). You will have to press the action key in order to use it.
Once you're at the top, STOP your character. You will probably notice a pile of rocks (#1). You will have to avoid these traps at all costs. Touching them would be equal to an instant (and painful ;-)) death. Wait for the right moment and go left. Destroy the crate and press the action key (#2). This will allow you to reach a second ledge safely.
You will have an opportunity to destroy even more crates. This will allow you to gather new gold coins. Now you will have to avoid TWO similar traps (#1). I guess I don't have to remind you to wait for a right moment to make a move. Use the sword once again (#2) in order to leave this area of the map.
You will find yourself near a large clearing. I'd strongly recommend that you start off by going towards the lower part of the screen. You will have to find a glowing spot (#1). Use it in order to get to the ladder. Once you're on a lower level, destroy a single crate and pick up the second pendant (#2). DON'T go right or you'll die (quicksand) and you'd have to repeat the entire level. Instead, use the ladder to go back to the clearing.
Now it would be a good idea to destroy some of the remaining crates (#1). Just as before, you should be able to find at least a few gold pouches. Go back to the area near the rocks. You should be able to locate a second ladder here, but you don't have to use it. Instead, start moving left (#2). Get ready for your first fight!
Once you've reached a new area of the map, you are going to be attacked by a large group of cannibals. I wouldn't recommend charging at them right away. Instead, destroy a nearby crate and pick up the third pendant. Otherwise you could lose it during the fight, because it would disappear after a few seconds (if you would accidentally destroy the crate). Now you may focus all of your attention on the natives (#2). Attack them.