(Full Rare+ Version)
An endless deluge of water spews forth from the primordial corruption of water, drenching the ground below with torrential downpour. The massive elemental itself is composed entirely of water or ice and typically manifests a form that closely resembles creatures of the deep sea, such as sea jellies, crabs, lobsters, octopus, sea horses, or sharks. It swims through the air as if underwater, intent on drowning the material plane in its element.
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DESIGN COMMENTARY
This primordial corruption was initially intended to be CR 25 (the lowest of the four) on account of its relatively lower mobility, but during the process I realized the water it gave off was pretty deadly. A couple of well-deserved bonus actions and reactions later, I can say it's incredibly deadly to fight against. The tendrils have a comparatively low To Hit bonus (+14 instead of +18 for its peers), but it makes up for it with exceptionally long reach (50 feet!) and multiple attacks (3, plus 1 extra one when creatures get too close). The tides created on ground will give any non-flying combatants a very tough time.
This might be my other favorite drawing. Though I don't think I properly depicted the wave + horizon interaction it's such a minor detail easily overlooked. I like how the colors developed across the blue/yellow spectrum, and that bloom was a really good final touch that sold the water aesthetic.