Primal monstrosities evolved to thrive in the harshest wintry environments.

The form of a gigantic wyrm made of ice towers over Grik and his soldiers. - Bogroot Demon (RPA-ADV6) 

Ice wyrms have giant mandibles for seizing prey, and rows of barbed teeth that line their inner mouths;

Instantly, the whole camp comes to life and scrambles to defend themselves as the ice wyrm opens its face, revealing a cavernous maw full of jagged fangs. - Bogroot Demon (RPA-ADV6)

The spawn of an ice wyrm is a harmless ice slug;

You set the starfish and ice slug down at the base of the mangrove. They start to race up the side of the tree.

You let your starfish and ice slug explore the ancient observatory together. They find a private corner and have a little chat. - Bogroot Demon (RPA-ADV6) 

An ice wyrm was brought to the King's Guard Camp in Bogroot Swamp from Iktel, Plane of Frost, by the Demon Elsifor:

• Defeat it, and General Grik will move forward to the Abandoned Lands.
• Fail to kill it, and it will wipe out all the King's Guard soldiers.

An ice wyrm is one of the ferocious beast combatants in the Colosseum of Ashes:

An enormous ice wyrm breaks to the surface and slides into the arena. It opens its mouth, revealing a circular set of large, jagged teeth. - Tome of Encounters (RPA-Tome-SQ1-88) 

• Kill the beast, and enjoy your victory. The beast is killed, succumbing to its multitude of injuries.
• It freezes the arena with its icy breath, and the guards are left to clean up the mess.

A Starlit Door cultist with an ice wyrm fights a Halfling loyal to the King's Guard and Jara of the Dragul in Iktel, Plane of Frost at the final battle of Brizoor Waal.

After the battle with the ice wyrm, a mortally wounded elven guard is being cared for by a frogkin healer.

• Salute the elf for upholding the the duty of a Kings guard.
• Praise the elf for her sacrifice to save others.