|Main leader||King Ymiron (presumed)|
|Secondary leaders||Kreug Oathbreaker|
Frost vrykul |
|Base of operations||Icecrown Citadel, Pit of Saron, Ymirheim, Utgarde Pinnacle|
|Theater of operations||Icecrown, Howling Fjord|
The Ymirjar are the elite warrior caste of the Lich King, the victorious vrykul in the battle of ascension at Jotunheim. They inhabit the city of Ymirheim in the center of Icecrown, which is of most significance to vrykul culture. The losers become cursed vargul.
Had King Ymiron blown the horns and called for all of the leaders of the Ymirjar and mjordin alike, the vrykul would've become a force more powerful than any other within the Scourge. This action would've organized the vrykul nation.
The concept of ascension is communicated to the vrykul through a huge scroll made from dragon skin. The scroll depicts a vrykul thane, surrounded by angelic-looking beings, ascending into the heavens and transcending death. A mysterious, darkened figure looms large in the picture's background.
What "ascension" exactly implies is unclear. Some Ymirjar are frost vrykul with the Undead classification, others are frost vrykul with the Humanoid classification, several frost vrykul has been shown not to be Ymirjar at all, and there are also Ymirjar vargul despite vargul being said to be the losers of the challenges for ascension.
It is possible that the rewards for ascension are becoming "good" undead like the death knights are (and in opposition to the flawed vargul), or that the vrykul are cleansed of the flaws of the Curse of Flesh. It is also possible that simply the honor of being part of the Lich King's elite warrior caste and living in Ymirheim could be considered a reward by the vrykul.
- Skadi the Ruthless is presumably among their ranks, due to his appearance and the fact he is surrounded by Ymirjar himself.
- Halof the Deathbringer, Overthane Balargarde and the female Scourge Banner-Bearers are frost vrykul living in Icecrown, making them possible members as well.
- The Frostwarden Warrior, Frostwarden Sorceress and Frostwarden Handler in Icecrown Citadel could be Ymirjar.
- Finally, the frost vrykul who defended Angrathar during its battle were probably Ymirjar as well.