Finding Red skulls...
	Various Steam Achievements...

Red skulls can only be found in the fortresses during infiltration missions. Once the main assaults begin, they will disappear.

Achievement	How to unlock
Assassin of Assassins	Locate and kill a Legion Assassin.
Berzerker	Kill 200 Legion soldiers.
Blinded To Fear	Kill 50 Legion without using a health potion.
Champion of Champions	Find and defeat a Legion Champion.
Deadly Axe Juggler	Kill 5 Legion just using Throwing axes.
Death King	Finish off 150 Legion with fatality moves.
Demon Eviscerator	Finish off 100 Legion with fatality moves.
Demon Hacker	Finish off 25 Legion with fatality moves.
Demon's Nemesis	Kill Hel's Harbinger Drakan.
Dragon Master	Complete the second dragon gem, and summon a dragon.
Dragon Overlord	Recover the final dragon gem, and summon a dragon.
Dragon Summoner	Find and charge the dragon gem Hugin and dragon amulet, and summon a dragon.
Euthanasia Euphoria	Use your defensive bash to knock your Legion foes to their doom!
Friend Of The People	Power-up over 500 Vikings in your armies with runic magic.
Galcliff Supplies Freed	Liberate the farm, still, lumber mill, and the quarry in Galcliff.
Giant Killer	Find and slaughter a Legion Giant.
Heimdall's Enforcer	Glacially wipe out a Legion using the ultimate ice attack.
Hero Of Caldberg	Lead your army to victory at the battle for Caldberg.
Hero Of Darkwater	Lead your army to victory at the battle for Darkwater.
Hero Of Holdenfort	Lead your army to victory at the battle for Holdenfort.
Hero Of Midgard	Lead your army to victory at the final battle for all Midgard.
Hero Of Thornvik	Lead your army to victory at the battle for Thornvik.
Isaholm Supplies Freed	Liberate the farm, still, lumber mill, and the quarry in Isaholm.
Killer of Champions	Kill 10 Champions.
Killer of Giants	Kill 5 Giants.
Lust For Blood	Kill 100 Legion soldiers.
Niflberg Supplies Freed	Liberate the farm and the quarry in Niflberg.
No Need For Immortality	Lead your army to victory at Hel's Fortress without need for immortality.
Odin's Doomsinger	Use the ultimate fire attack to kill a Legion.
Redeemer of Galcliff Hard	Liberate Galcliff completely on the hard difficulty level.
Redeemer Of Galcliff Normal	Liberate Galcliff completely on the normal difficulty level.
Savior of Niflberg Hard	Liberate Niflberg completely on the hard difficulty level.
Savior of Niflberg Normal	Liberate Niflberg completely on the normal difficulty level.
Secretive Rogue	Complete the quest to sneak into Darkwater.
Skullbagger 1	Collect the 6 skulls in Darkwater.
Skullbagger 2	Collect the 6 skulls in Holdenfort and the 6 skulls in Caldberg.
Skullbagger 3	Collect all the 4 skulls in Thornvik.
Slaughter Master	Kill 500 Legion soldiers.
The Flames of Freya	Buy flamepots and incinerate 10 Legion soldiers with them.
The Perfect Killer	Kill a Legion Champion without being hit.
They Never Saw Me Coming	Execute 100 sneaky kills.
Thirst For Blood	Kill 50 Legion soldiers.
Thor's Mortal Lightning Rod	Send a Legion back to the underworld in the most lightning-tastic way imaginable.
Viking Blademaster	Learn all the moves in the game.
Viking Butcher	Master the first new move at the Battle Arena.
Viking Conqueror Hard	Reach the end of the game on hard difficulty.
Viking Conqueror Normal	Reach the end of the game on normal difficulty.
Viking Slaughterer	Learn a total of 4 new moves.
Viking Slayer	Master a total of 8 new moves.
Viking Warrior	Master a total of 12 new moves.