Weapon (heavy crossbow, requires attunement), legendary
Wavebreaker is a +1 heavy crossbow without the loading trait. It is typically carved from whalebone or the shell of a titanic mollusk or crustacean, decorated with intricate scrimshaw and nacreous inlay and with a bow and mechanism of gilded steel or similar rust-resistant metal. Ammunition shot from a wavebreaker is antithetical to any aquatic or watery creature (any creature with a swim speed).
If an aquatic creature takes damage from an arrow shot from the wavebreaker the creature must make a DC 17 Constitution saving throw, taking an extra 6d10 piercing damage on a failed save, or half as much extra damage on a successful one. This bane effect once used can’t be used again until the next dawn. In the meantime, the wavebreaker can still be used as a magic weapon. Additionally, water does not provide any situational benefit (for example extra cover or disadvantage) against attacks made with a wavebreaker.
Finally, you can target a creature or spell that is watery by nature within 30-feet as an action.
You automatically hit if it is a spell. If the target is a creature you must make a normal attack roll against the creatures AC. On a hit, wavebreaker deals no damage but acts as dispel magic against the spell or a banishment against non-native creatures (for example a summoned water elemental). You can use this ability as often as desired but a creature or spell that is not dispelled or banished becomes immune to this effect for 24 hours.
Pirate Campaign Compendium © 2018, Legendary Games; Lead Designer Jason Nelson. Authors: Alex Augunas, Jeff Gomez, Matt Goodall, Jim Groves, Tim Hitchcock, Victoria Jaczko, Jonathan H. Keith, Lyz Liddell, Thomas J. Phillips, Alistair J. Rigg, Alex Riggs, Loren Sieg, Neil Spicer, Todd Stewart, Rachel Ventura, Michael D. Welham, Linda Zayas-Palmer.