Curse of Sea Legs

This curse gradually transforms the afflicted's legs into crab legs or octopus tentacles upon returning to land, with the transformation eventually spreading to their entire body, while staying at sea is known to halt its progression. he target must make a Wisdom saving throw (DC 17), which is modified by the Curse Strength Table. On a successful save, the target becomes aware that somebody attempted to curse them. On a failed save, the target becomes cursed. Upon the completion of this curse’s triggering event, the target automatically advances to stage 1 of this curse.

Triggering event

The next time the cursed creature goes at sea, their legs are cramped and itchy.

Stage 1

The cursed creature speed is reduced by 5.

Stage 2

The cursed creature becomes obsessed with the sea. The curse creature's legs become that of a crab or octopus.

Culmination

Upon failing the final escalation check, the cursed creature entierly transform into a crab or an octopus. If the creature is a player character, they become an NPC under the GM’s control.