There is a corpse to your right just after you finish climbing down the cliff face. He holds a scroll.
Here, in the area where you fight the two skeleton warriors, you’ll see this corpse.
Light Magic Gem #1
To the left of where you find scroll #2, there is a fallen titan that you can climb. Do so, then drop down on the other side to find a fallen knight carrying a gem.
Life Magic Gem
BEFORE you use the rune to move the titan’s arm, run along the arm and you’ll reach a small island holding a dead knight.
Once you have moved the titan arm using the rune, follow the new path. Leap to the fallen titan on the right, then continue right and jump across to another area that contains a fallen knight and a bag of holy water.
After you jump to the fallen titan on the left, work your way around the front of the titan to find a dead Brotherhood knight holding a Shadow Gem.
Light Magic Gem #2
Once you activate one of the two rune slots on this titan, it will raise its arm. Climb up and leap from this extended limb to reach the next area. There will be a corpse partially hidden by destructible debris right where you land.
Light Magic Gem
At the first fork in the road, choose to go right. You’ll see a dead knight on the other side of a large gap. You may not be able to jump the distance, but that’s ok, you can drop down safely and climb up the other side.
Just in front of your after the first cutscene with the Chupacabra.
Life Magic Gem #1
Head left after the Chupacabra cutscene and you’ll find this poor sap. He’s got a life gem.
Head right after the Chupacabra cutscene to find this corpse holding a scroll.
Life Magic Gem #2
Near the back of the puzzle area, in a small nook as seen above.
Right across from this Neutral Element Fountain you’ll see a dead knight. He’s got a scroll for you.
Shadow Magic Gem
When you reach the point pictured above, climb up but shimmy to the right. You’ll reach a fallen Brotherhood knight holding a Shadow Gem.
Hint Scroll #1
There is a fallen knight here, not far from the start of the level. He’s got a hint scroll for the puzzle ahead.
Shadow Gem #1
After you solve the calendar puzzle, run around to the left side and drop down. You’ll find a corpse with a Shadow Gem.
Hint Scroll #2
Right next to the second puzzle is the hint scroll for the second puzzle. Makes sense…
Life Magic Gem
After you encounter and defeat the Reapers for the first time, run to the left and toward the camera. You’ll drop down into an area where you can see a dead knight. If you’ve been collecting all of the Life Gems so far, this will be the final one the game has to offer.
Light Magic Gem
After you defeat the first Necromancer, head into the portal on the right. In the next area, you need to use the portal on the left side to grab the hook point, then jump backward and land on the ledge with the corpse on it.
This is the final Light Magic Gem of the game.
Here, next to the bag containing a dark crystal on this floating rock.
Shadow Gem #2
Near the end of the level, you’ll end up teleporting right next to a health fountain.
Head left and down the twisting steps and you’ll find the final Shadow Gem.