From publisher blurb: A warlock who serves the sauter-méduse pledges themselves to find powerful magical artifacts for their patron to feed on, and grow fat from. The eldritch beast beneath the waves resembles a gargantuan jellyfish, with tendrils hundreds of feet long, who consume and contains vestiges of arcane power like a living, hungry vault. Their warlocks borrow power in the form of these tendrils and power over magical items, sometimes of their own free will, and often to earn the safety of themselves or their homes. This product features the otherwordly patron option a warlock can take at 1st level, seven eldritch invocation options they may take, and the NPC stat block for the sauter-méduse itself, a CR 22 elemental complete with lair actions and relevant lore.