n huge amphibious cold elemental water 

Perception +19; darkvision

Languages Aquan

Skills Athletics +21

Str +7 Dex +7 Con +5 Int -1 Wis +5 Cha +3

AC  30; Fort +20, Ref +21, Will +17

HP 185; Immunities bleed, cold, poison, paralyzed, sleep; Weaknesses fire 10

Explosion (cold) When the icewyrm dies, it explodes, dealing 8d6 cold damage to each creature in a 10-foot emanation (DC 27 basic Reflex save).

Speed 25 feet, ice burrow 20 feet, swim 60 feet

Melee [>] jaws +23 (reach 15 feet), Damage 2d12+13 piercing

Melee [>] tail +23 (agile, reach 15 feet), Damage 2d6+13 slashing plus 1d6 persistent cold

Ranged [>] ice shard +23 (range increment 60 feet), Damage 1d6+13 piercing plus 1d6 persistent cold

Breath Weapon [>>] (cold, evocation, primal) The icewyrm breathes a 60-foot line of freezing shards of razor-sharp ice, dealing 3d12 cold damage and 3d12 piercing damage to every creature in the line (DC 29 basic Reflex save). The icewyrm can't use Breath Weapon again for 1d4 rounds.

Ice Burrow The icewyrm can Burrow through ice or snow with a Speed of 20 feet. It moves at its full burrow Speed, leaving no tunnels or signs of its passing.

Bestiary 2, page 115. Expanded in LOIL.