To get hideout fragments in Tribes of Midgard, you will need to locate hideouts in the Smokey Highlands region and clear each hideout level fully.
What this means is that you will need to kill every single enemy. If you don't, you will not get your hideout fragments required to unlock the lair that houses Fenrir, the saga boss.
So as we stated already, you can find hideouts in the Smokey Highlands region of the game, and what these locations will look like are basically giant caves in the middle of the desert region.
Going inside the cave will bring you face to face with either horde of goblins and Brennalfar warriors and archers and Trolls. Sometimes there will also be werewolves, but they are pretty rare.
However, before heading straight into hideouts, we highly recommend having at least rare and above weapons and armor and a power level of at least 220+.
You can get both better weapons and armors and raise your power level by upgrading the armorsmith and blacksmith. Once upgraded, you will be able to make better armor, and doing so will raise your power level by a lot.
Leveling up is also another option for getting higher power levels in Tribes of Midgard. Do all of this, and you should be able to clear hideouts with no problem, just remember to pack some potions and take it slow.
Check out some more Tribes of Midgard guides at Pro Game Guides!