Shipwreck the sharpedo/carvanah. It must know surf and crunch (two powerful STAB moves so your welcome) and one more attacking move and one non-attacking move of your choice. Surf to take down the ships and crunch to eat or maul its puny victum. Shipwreck must always start out with surf when battling a water type (ship). When Shipwreck is vsing a NFE pokemon that isnt a water type, it must use crunch (eating puny victums). Shipwreck sees him/herself as a pirate, so whenever Shipwreck gets a status condition, you can't use potions or pokemon centers (full restores don't count as potions), instead you must use a berry to protect Shipwreck from its status condition and scurvy. Also acting like a pirate, Shipwreck loves treasure, so he/she must always be holding an amulet coin.
In other words, must start with surf vsing water types and start off with crunch vsing NFE/non-water types. Can only use berries to cure status condition and must always hold amulet coin.
Move set:
Surf (must keep)
Crunch (must keep)
Attack (your choice)
Non-attack (your choice)
Also forgot to mention, Draco or whatever the Dragon type E4 dude is named, is also a pirate. Shipwreck, being jelouse of his hat, must solo at least three of Draco's Pokemon or solo Draco's highest leveled Pokemon.
Goodluck!