Sam must pass through the Serpent Yards to get to his main objective; the Sun Pyramid, which is where the Time-lock lies.
- When exiting the starting building, head for the lower right corner of the area to collect an ammo pack.
- Opposite of #1, to discover a "suicidal plant" (Beheaded Kamikaze). Do not kill him or destroy the plant until the secret has been registered.
- In the part where the Kleers come in, when you're in a lower-height area with a mini-pyramid in the middle, a few Major Bio-mechanoids will come bursting through the walls of where you came front. Walk up to the remains and turn left to find a secret Large Health.
- After the force field, go behind the right house to find some Cannonballs.
- (HD-only) In the building in front of the force field, on its left side is a bush. Destroy the bush or crouch past it and activate a switch. This will trigger a bouncing Kamikaze that will bounce high in the air in the area you are (Hint: His first bounce is near the exit, just look up and left from your current position). When you kill him, some Sniper ammo and health pills will appear.
- (HD-only) In the yard before the moon pyramid, next to the structure with the statue that will shot fireballs is a doorway with a statuette above it. Blow up the statuette to turn the doorway into a portal to a secret location.
- After you pick up the Ix Chel mask in the Moon Pyramid, head right of the entrance and approach a small head statue. It will turn into a Marsh Hopper. Let it explode on you or blow it up with a rocket to reveal a Super Health. If you blow up the head but the Marsh Hopper is still alive, kill it and the secret will register.
- Go around the Moon Pyramid until you find a detonator switch behind it. Use the switch, and the pyramid will be blown up, and 2 Highlanders will spawn afterwards.
- Back in the yard before the Moon Pyramid, after placing the Ix Chel mask on the alter, and the fireball-shooting statue is destroyed, enter the building it was on to find a secret Extra Large Armor.
- In the upper right corner of the last courtyard is a health pill, pick it up to reveal a "secret watcher" (look above to notice the secret watcher).
- Shoot the "secret watcher"'s eyes to turn him into the "mighty kamikaze". You better take some distance though, as he has a massive explosion radius.
- In the last room, blow up the two jaguar statues above the exit of the level to reveal a secret Large Health.
Before the pyramid part, where the Kleers spawn, instead of going down the stairs,take right to the ledge, until you reach the buildings. Two Major Bio-mechanoids will spawn. After taking them out, proceed to the rightmost top corner of the village to find a phone booth, which you can use to hear a conversation.