Grahl:
-Between Snowclad Ruins and Benkongerike (2)
-Near Brodir Grove
-Dragon Mound near Vahlok's Tomb
-Near the Abandoned Lodge
-Within the DLC2LCharAnimalMountainSnowPredator and DLC2LCharAnimalForestPredator leveled lists (various locations; random creature selected, dependent on level and encounter zones). Note that I have replaced the Troll entries in these leveled lists, since the Grahl is Solstheim's species of troll.
-NEW: Forgotten Vale (6)
-NEW: Glacial Crevice (1)
-NEW: Within the LCharAnimalSnowFields leveled list (several northern, frozen locations in skyrim; random creature selected, dependent on level and encounter zone). 


Armored Grahl:
-Glacial Cave
-Castle Karstaag Caverns
-Castle Karstaag Ruins (2)
-Near the airship ruins in Moesring Pass
-Bristleback Cave
-Broken Tusk Mine
-Benkongerike


Follower:
An Armored Grahl in Thirsk Mead Hall is available as a follower if you become the riekling chief. Note that he uses Riekling subtitles (can't fix) and that grahls are very slow. He is Protected, so only you can kill him.

Grahls are stronger than Frost Trolls due to their claws, tusks, and heavier build, but they are also slower due to their bulkiness.

Stats relative to Frost Troll (Grahl, Armored Grahl):
-Health +100, +50
-Damage +25, +25
-Armor +0, +75
-Health Regen -50%, -50%
-Stamina -100, -150
-Stamina Regen, -50%, -50%
-Speed -25%, -25%
-Acceleration -50%, -50%

Note that the Armored Grahls have some lowered stats because I didn't want them to be overpowered (especially since they usually have Riekling allies). The Armored Grahl follower does not have any decreased stats though.

LEFT: Grahl in Elder Scrolls Legends (2017). RIGHT: Grahl in TES3 Morrowind: Bloodmoon DLC (2003)

My Grahl is mostly based on the modern troll-like depiction in Elder Scrolls Legends. The Morrowind original had a more boar-like head; however, it should be noted that it was named "Ice Troll" in the game files, and this was before Bethesda designed their first* ape-like troll in Oblivion. So I think it makes sense that grahls would've resembled trolls if they were redesigned for Skyrim.
*(Udyrfrykte was baboon-like, but he wasn't described as a troll until later games.)

In order to fit in seamlessly with TES5, I've found the best technique is to use a TES5 resource as the base. So, I began with the Frost Troll model and made the following changes:
-Tusks added to upper jaw
-Tusk/horn replacing third eye
-Ice spikes
-Hunched back
-Thicker abdomen and fattened belly
-Lengthened claws
-Thin, gangly arms
-Slightly thinner legs
-Major restructuring of head and face for a unique look:
---Jaw, lips, and gums reshaped to accomodate tusks
---Rounder head without the oblong cranium
---Nostrils enlarged and brought forward to create a short, wide snout
---Eyes rotated and moved outwards -- less "binocular" than a troll
---Wide upper jaw, narrow lower jaw
---Upward-curving ears
-Version 1.1.0+: unique texture with blue skin and red eyes (thanks to Kajaun for allowing me to use and modify his TROLL texture!)

Requirements:
-Dawnguard
-Dragonborn

Installation:
Standard. Use a mod manager or extract the files to your Data folder.
If you want the high-res texture option or the old vanilla texture, check the downloads tab.

Uninstallation:
Revert to an old save from before installation, and disable/delete the mod.

Compatibility:
-If you have other mods that edit DLC2LCharAnimalMountainSnowPredator, DLC2LCharAnimalForestPredator, or LCharAnimalSnowFields leveled lists, you will want to make a Bashed Patch (otherwise the one last in load order will control the leveled lists).
-This uses textures from the Mammoth, Riekling Chief, and static icicles -- any retextures of these will alter the Grahl's appearance (hopefully for better ;).