The following is an adventure idea. While set within my own homebrew campaign, the scenario and magical item presented are generic enough to be used in any D&D campaign. No NPC levels are indicated, allowing the DM to customize its power level to suit his players.
Someone or something is attacking the merchant ships in the water surrounding Vakarös. Within the past six weeks, twelve merchant vessels have been boarded and stripped of their valuable cargo. The crews have been slaughtered, leaving the decks awash in gore. The attacks have left no survivors, but the harbormaster and the sea-watch have reported that some of the crews have been hacked apart, while others bear wounds inflicted by slashing teeth. Many of the old salts along the docks mutter grimly and lay the blame at the scaly feet of the dreaded “sea devils,” or sahuagin, who are known to have a city many days sailing distance to the north. If the sea devils are on the march, it is only matter of time before Vakarös itself comes under attack. The merchant lords of the sixteen houses of trade have pooled their resources and offer a sizable reward to whoever can identify and stop this menace.
The culprits of these attacks appear straightforward at first. With a known sahuagin city relatively close to the port, it seems logical that the sea devils are to blame. With their fierce reputation and savage ways, it’s easy to shoulder the blame upon their scaly shoulders. This is of course exactly what the real culprits hope.
The attacks are in fact the work of a band of pirates, led by the Captain Eree Nuz. Captain Nuz is normally a mediocre pirate, and if not for a random bit of luck, would have spent his career taking lightly defended ships before vanishing into obscurity. As Chance would have it, the Captain and his crew stumbled upon the smoking remains of a tiny tribal village while taking on stores of water several weeks ago. The village had been raided by a neighboring tribe, who killed most of the men and elders in the village, and carried off the rest as slaves and future meals. The sole survivor was the village witch doctor, who fled the village after being gravely wounded in the raid. Nuz and his crew would have normally left the old man to his fate, had the witch doctor not offered to provide the captain and his men powerful juju in exchange for saving his life. Looking for any edge he could possibly get, Nuz agreed and took the witch doctor aboard his ship.
The “juju” that the witch doctor has provided are potions of the sea fiend. A single draught of a potion always the drinker to assume the form of a half-man/half-shark for a limited time, transforming Nuz’s mediocre pirates into fierce sea raiders for the duration of their attacks on ships. The ability to approach a ship undetected and surprise its crew has proven the pirates unstoppable so far.
What Nuz and his men don’t know, however, is that with each use of the potions, the chance of the condition becoming irreversible grows. The witch doctor is aware of this slight problem, but has so far kept it to himself. He hopes to escape from Nuz and his men before they become aware of this. Unfortunately, the pirates have no intention of letting the witch doctor escape, holding him under constant guard both aboard ship and while in their camp.
Depending on the DM’s desires and the PCs actions, the sahuagin red-herring can be played out for some time. Ultimately, however, events should take place that put the party onto the right path. This may be accomplished in several ways.
Should the characters accompany a likely target ship, they might find themselves in the thick of the action as the pirates attack them at sea. Similarly, the party may chose to stake out the sea lanes, either by using themselves as bait or employing magic or stealth to observe potential targets or threats. In both cases, a rollicking battle aboard ship may ensure.
If a more land-based encounter is desired, the party might be patronizing a local wharf-front tavern when a gang of pirates comes carousing. One or more of the pirates has consumed a potion of the sea fiend prior to their night out. In the midst of a heated card game or brawl, the pirate(s) assume the vicious man-shark form and proceed to inflict heavy casualties on nearby patrons. Capturing one of the pirates leads to the location of the pirate camp, hidden in a secluded cove, allowing the party to stop the threat at its source. Should the DM wish to add another level of intrigue, the pirate(s) had consumed enough potions to make the effects permanent, leaving the party with strange half-man, half-shark corpses at fight’s end and more questions than answers.
In the final showdown between the party and the pirates, the witch doctor will not hesitate to assist the party, but will attempt to escape from both the pirates and the adventurers when opportunity allows. Characters of a lawful persuasion might wish to bring him to justice. After all, it was his magic that allowed the pirates to plunder so many vessels. This pursuit of justice could lead the party deep into the surrounding jungles, where perhaps the witch doctor has sought refuge in an ancient temple or ruined city.
New Magical Item: potion of the sea fiend
Drinking this potion gives the imbiber the ability to assume the terrorizing shape of a man-shark hybrid. Towering some 7 to 8’ tall, the form resembles a humanoid shark with webbed feet and stubby semi-human hands. Its head is that of a mako, tiger, hammer head, or great white shark. The effects of the potion last one hour, during which time the character can assume the man-shark form once, and return to normal form once, at will. In any case, at the end of the potion’s duration, the drinker returns to his normal form.
The potion acts similar to a potion of heroism, granting temporary HD to the imbiber. A zero-level man gains 4 HD while in shark-form. A 1st-3rd level character gains 3 HD, a 4th-6th level drinker gains 2 HD, and a 7th-9th level character gains a single HD. Characters greater than 9th level gain no additional Hit Dice. Any damage take while in man-shark form is deducted from the temporary hit points gained in the transformation. Unlike the druid’s ability to change form, returning to normal shape recovers no lost hit points. Additionally, while in this form, the drinker’s higher thought processes are suppressed, making him more bestial and aggressive. His Intelligence suffers a -4 penalty until he returns to normal shape. While the man-shark form may seem to be a type of lycanthropy, it is not. The imbiber gains no special protection against attacks, and silver, magic weapons and wolvesbane are no more effective than against a normal man.
While in this hybrid form, the drinker can use simple melee weapons such as clubs or swords, but cannot use missile weapons more complex than thrown weapons. He cannot speak or cast spells. Any items, clothing, armor, etc. on the character is automatically shed during the transformation, remaining on the ground where the change occurred.
Potions of the sea fiend have a potentially serious side-effect. With each potion consumed, there is a cumulative 5% chance that the man-shark form become permanent when assumed. If this occurs, the only cure is a remove curse or some version of a wish spell. Even death will not restore the drinker to his normal form.
While in the hybrid form, use the following stats for the imbiber:
Sea Fiend (man-shark)
Armor Class: 5
Hit Dice: 4 to 10
Movement: 9, Sw 18
THACO: 4 HD – 17, 5 to 6 HD – 15, 7 to 8 HD – 13, 9 to 10 HD – 11
# of Attacks: 1 bite
Damage per Attack: 4 to 6 HD – 3d4, 7 to 9 HD – 4d4, 10 HD – 5d4
Magic Resistance: None
Special Attacks: None
Special Defense: None
Morale: Steady (11)
Size: L (7 to 8’ tall)
XP: 4HD – 120
5HD – 175
6HD – 270
7HD – 420
8HD – 650
9HD – 976
10HD – 1,400