Krakens are fearsome creatures of legend.
- "The Greyjoy sigil is the kraken: what it grasps once, it will never surrender."
- ―Theon Greyjoy
Krakens are legendary, massive cephalopods that are said to stalk the world's oceans. They are largely held to be mythical, though sailors occasionally report seeing them.
A golden Kraken on a black field is the sigil of House Greyjoy.[1]
In the books
There have only been unconfirmed reports of krakens. Some say that they're just the figments of the wild imaginations of drunken sailors, similar to wild reports of "mermaids" by sailors who have been out at sea too long, which turn out to just be sea cows. Others adamantly insist that in a world where dragons once stalked the skies, krakens might live in the deep oceans. If krakens do really exist, they are extremely rare.
Exact descriptions of "krakens" look like in real-life legends vary, but the mythological kraken in the A Song of Ice and Fire novels is specifically said to resemble a giant squid.
See also
Kraken on A Wiki of Ice and Fire (spoilers from the books)
Kraken on Wikipedia
References
Template:Creatures