The World - Lake Lakira
Said to have been created by the same forgotten mage who founded The Keep, this lake is extremely deep, and suited perfectly to endless varieties of creatures. Sweet watergrass and moss grow along the bottom, delicacies that change with the seasons. During winter, it is kept heated through ancient magic, and the animals that call it home enjoy having magis escape the cold by diving in.
If the heat gets too stifling, shrug off your robes or traveling clothes and take a swim - there's no lack of playmates. If you dive deep down, you can see where the young hatchlings have created piles of treasures - sparkly rocks and the odd scale. Swim near a koi fish, and it will give you the temporary power to breath beneath the lake.
This is where basic training lessons take place, if you possess a koi or any other watery beast. Basic things like being able to ride a kraken or leviathan are taught here, where there is no immediate danger. The finer arts of learning to swim next to your koi and breath under water are conducted here as well.
Exploring deep enough, you can find a wide tunnel large enough to let a leviathan pass through. You don't follow it, knowing you'll run out of air, but you know this is how the creatures are able to travel to the nearby ocean when they tire of the lake. When you've exhausted yourself with diving, ask one of the young krakens and you can receive a throw in the air, sparking a game among the hatchling of catch-the-mage.
Dry out under the sun afterward on a hot rock, alongside basilisks and the occasional cat, before you trudge back to The Keep on the well worn path.