Frillish and Jellicent

Our first jellyfish pokemon since the Tentacool line are a very far cry from those menacing, almost more squid-like poison types. These regal cnidaria resemble an adorably, frilly "prince" or "princess" depending on gender, but they're also the first-ever water/ghost combination, and said to drag paralyzed prey miles below the ocean to be consumed.

When Frillish evolves into Jellicent, it takes on a bigger, older, kinglier or queenlier appearance, fairly comical if not for the blank, ghostly stares and the dex's tales of nautical horror:

"All sunken, all lost, all vanished." Dear lord. These goofy ghoulies don't mess around, do they? An absurd pink kissy face or the phantom of a pringles can might be the last thing a ship's crew ever see.

Spookular deep-sea slimers.