D&D 5E - The Rise of Tiamat

Episode 2: The Sea of Moving Ice
Far to the north, beyond the Spine of the World and
above even Icewind Dale, lies the Sea of Moving
Ice. Gigantic icebergs wander listlessly through
this glasslike sea, or are sent smashing and grinding
against each other by bitterly cold winds, the sea spray
transformed into fantastic frozen shapes around them.
Only creatures adapted to severe cold can survive such
frigid extremes, but many beasts—and even people—
make their homes in the Sea of Moving Ice. One such
creature is the white dragon Arauthator, known as “Old
White Death” by those he stalks and terrorizes. In this
section of the adventure, the heroes’ battle against the
cult leads them to one of Arauthator’s iceberg lairs.
"The Sea o f Moving Ice was the last known location o f the
Draakhorn. No one can pinpoint its present location from
the sound, or even verify with certainty that the relic is still
in the northern sea, but the search must start there.
“The one person who could tell us more is a tiefling
sorcerer called Maccath the Crimson. No one alive knows
more about the Draakhorn than her, but the Arcane
Brotherhood, o f which she is also a member, hasn’t
seen her for three years. She was investigating the Sea of
Moving Ice when she disappeared.”
T h e D r a a k h o r n ’s G a l l
Each time the Draakhorn sounds out, its unearthly call
echoes across the Sword Coast. Dragons hear it plainly,
even as other creatures hear it only as an indistinct
moaning when their surroundings are quiet and the
wind blows just right. Creatures that cannot hear the
Draakhorn can still sense it, like a faint vibration felt
subconsciously and interpreted as a sense of dread.
The adventurers were introduced to the Draakhorn by
Dala Silmerhelve during the first session of the Council
of Waterdeep. When they are ready to seek more
information on the ancient relic, Dala provides it.
“O l d W h i t e D e a t h ”
The white dragon Arauthator haunts the Sea of Moving
Ice like an avenging wind. Personifying the brutality and
savagery of his kind, Arauthator is a solid ally of the Cult
of the Dragon, and can be counted on to be present at
the Well of Dragons when Tiamat makes her triumphant
return from the Nine Hells.
Arauthator’s chief lair is beneath a remote peak
known as Lonefang Mountain, but he maintains a
number of smaller lairs among the icebergs that drift
with the seasonal tides in the Sea of Moving Ice. One
of these is known as Oyaviggaton (“island of eternity”)