In Serious Sam: Siberian Mayhem there are a total of 5 chapters that contain a wide range of hidden secrets and collectibles. Getting them all will net you with the Sam the Explorer and No Stone Unturned trophy achievement
This page will be covering Chapter 3: Siberiade, which contains 27 collectible secrets altogether.
- SECRET 1/27: Oil Elementals – Head south and continue to follow the quest marker. When you reach a bunch of rails stop. There will be several inactive machinery here, hit the button on each one to activate them. After you are done activating them all, the oil elementals will appear, give them a taste of lead.
- SECRET 2/17: Hoverboard Scooter – Continue to follow the quest marker, stop when you reach a large rock next to a machine. Head up this rocky hill in order to find the collectible
- SECRET 3/17: T.A.C.T – Follow the path left, when you come to the dead trees turn and head right. Ride through the bunch of trees on the opposite side. There should be a monument nearby with the next collectible
- SECRET 4/27: Explosives – Continue along the snowy track, into yet more trees. There will be an abandoned building to the left. The collectible is here on top of the water tank
- SECRET 5/27: Rage Serum – Keep following the track, this time stop when you reach a bunch of rocks and a rail behind them. Head under this rail, nearby there will be a hole in the ground follow it.
- SECRET 6/27: Time Warp – Activate the Hide and Seek optional objective and follow it to a cliffside on the left. The collectible is on top of the cliffs.
- SECRET 7/27: Rockets – Head towards the hangar area and the collectible can be found amongst the boxes next to the building with the truck
- SECRET 8/27: Skillpoint – For this one you are required to find all 3 Violet Keys. After acquiring the necessary keys you can then head inside the church. The collectible can be found here.
- SECRET 9/27: Holy Kamikaze – Follow the quest marker to the graveyard area. The collectible is by the angel statue
- SECRET 10/27: Armor – From the statue continue on towards the quest marker and find the buildings with the scarecrow. One of these buildings will have a bunch of wooden logs, the collectible is here.
- SECRET 11/27: Shrine of Netricsa – Slightly north west of the log building there will be a small shrine.
- SECRET 12/27: Hostile Snowman – Head east of the shrine and in amongst the trees should be this Snowman. Destroy it
- SECRET 13/27: Trap – Head south of the Snowman, towards several buildings and you should be able to locate a tractor. Keep going and out in the middle of nowhere there should be a table with this collectible.
- SECRET 14/27: L.I.F.E – Head to the quest marker and follow the path east to reach a bridge. The collectible is under the bridge.
- SECRET 15/27: Classic Arena – From the last collectible keep to lower ground and continue east. You should come across a tunnel area, follow this tunnel. In the tunnel, head to the room to the north east there will be a button behind one of the machines, activate it. You can then return back to the previous room and head through the door.
- SECRET 16/27: Cannonballs – Head towards the quest marker and you will reach a building. In the area just behind here there will be a small abandoned shack, the collectible is just next to it.
- SECRET 17/27: T.A.C.T – To the west of the cannonballs and amongst the trees is where you want to be.
- SECRET 18/27: L.I.F.E – In order to get this one you will need to acquire the Red Keys. After acquiring the first Red Key there will be a tower nearby, climb it.
- SECRET 19/27: Hoverboard Scooter – Just a little west of the tower there will be an abandoned building. You can find the secret gadget here.
- SECRET 20/27: Hacked Drone – From the abandoned building you can then claim the next Red Key, go ahead and do so. From there make your way towards the quest marker, the marker will take you to a bunch of water cannisters and abandoned buildings. Use the small snowy ramp and jump inside the building to find this one.
- SECRET 21/27: Weird Potion – Continue towards the quest marker to find an abandoned windmill. Head past this windmill and continue down the path. Head towards the water, the collectible can be found behind the waterfall.
- SECRET 22/27: Depot – Quickly grab the final remaining Red Key. From there head to the water in order to find a pier, the collectible is under this pier.
- SECRET 23/27: Cannon – Near the last collectible there will be an abandoned building. The collectible is sitting at the rooftop of this building, simply fire the ceiling and it should drop.
- SECRET 24/27: Ammo Depot – Stick to the waters edge and you will come across another abandoned building. The collectible is here by the boat.
- SECRET 25/27: Bonfire Lit – At the quest marker there will be a large bridge, under this bridge there will be a hidden passage. The collectible is here
- SECRET 26/27: Railroad Employee – Head to the rail track on the large bridge, to the left there will be a train. Board the train, the collectible is inside.
- SECRET 27/27: Skillpoint – The final collectible is just by the trail track, it sits on the table.