Nautical Ball Lightning

This spell creates one ball of lightning for every 5 levels of the caster. Each ball can be sent to a different target, and balls of lightning are usually targeted at the members of a ship's crew. A ball of lightning is 2 feet in diameter and flies through the air to strike its target at a movement rate of 24. Once it impacts its target, whatever the target, it moves rapidly along nearby surfaces in random directions: up masts, along decks, down ladders, and so forth, at a movement rate of 12. If it moves within 15 feet of another living being, it “chases” that being until it strikes this new target, and then begins random movement until it acquires a new target, continuing this cycle until it becomes stuck at a certain location, such as the top of a mast or at the end of a yardarm (10% chance rolled each round after the first if the ball's current location indicates the possibility), or the spell's duration ends.

A ball of lightning inflicts 1 point of damage per level of the spellcaster each time it touches a living creature. It automatically strikes a living creature that is its initial target, provided the target cannot outrun it; if it acquires new targets after the first, it automatically strikes them if its movement and theirs could intersect in a given round. If a ball stops a certain spot (for example, reaching a dead end at the end of a mast or spar), the lightning starts a small fire on a roll of 5 or 6 on 1d6. Creatures at that same location take 1 point of damage per level of the spell-caster each round they are in contact with the ball.