Vampire Bat & Were-Vampire Bat (New Monster)

These are two new monsters for Holmes Basic, the first of which is featured in Area 6 of The Forgotten Smugglers' Cave adventure (which is indexed here), and originally appeared as part of my list of One Hit Point Monsters.

Illustration by Lore Suto

Vampire Bat

Move: 180 feet/turn flying
Hit Dice: 1/8 (1 hit point)
Armor Class: 3 (9 while attached)
Treasure Type: nil

Alignment: neutral

Attacks: 1 bite

Damage: 1 point

A native of subtropical climes, the vampire bat has of late begun appearing in certain temperate coastal towns, apparently escaping from traders importing them for clients unknown. Roosting in colonies of up to 50 individuals, often in the warmer caves of the near underworld, they venture out in smaller groups (2d6 bats) to feed on livestock, other mammals, or even humans. 

When suitable prey is located, the bats will silently swoop down and attack from behind (surprise on 1-5 in 6, attack at +4). A hit inflicts a point of damage and allows a bat to attach and, unless stopped, automatically drain another point for each of the next two rounds (thus, three points total), before detaching and flying away. Attacks on an attached bat are against armor class 9, but a miss with a weapon will automatically hit the victim for a point of damage. Unattached bats will continue attacking in an attempt to distract the prey from disturbing attached bats.

For each round of attachment, there is a 1% chance that a bat will transmit a rare form of lycanthropy, causing the victim to become a were-vampire bat (see below) in 2d12 days.

Established colonies produce a layer of pinkish guano across the floor of their cavern, which which produces an acrid smell that can be detected from a distance, and is prized as a fertilizer (20 gp per bucket). Due to the strength of the odor and slippery consistency, any melee in such areas is conducted at a -4 to hit, with a natural 1 indicating a slip and fall.

The bats sleep soundly in the lair during the day, but any activity in the lair has a 1 in 6 chance per character (e.g., 2 in 6 chance for 2 characters) of waking the bats. Once disturbed, all of the bats of the colony will join in on a frenzied attack on the intruders.

It is rumored that larger forms of the vampire bat exist in the tropics.

Were-Vampire Bat

Move: 120 feet/turn flying (giant bat form) or 60 feet/turn flying or 120 feet/turn walking (man-bat form)
Hit Dice: 2 + 2
Armor Class: 3 (giant bat form) or 5 (man-bat)
Treasure Type: C

Alignment: neutral/lawful evil

Attacks: 1 bite (giant bat form) or 1 bite and 2 claws (man-bat form)

Damage: 1d3 (giant bat form) or 1d6/1d3/1d3 (man-bat form)

The unfortunate victims of the vampire bat may, on occasion, be inflicted with a rare form of lycanthropy, eventually transforming into a were-vampire bat. Like the were-rat, the were-vampire bat may take three different forms: human, giant bat, or horrible hybrid man-bat. As with other lycanthropes, it is immune to normal weapons in the latter two forms. In man-bat form, it is less agile but stronger of limb, and able to attack with claws in addition to biting.

If possible, the were-bat will roost and hunt together with a colony of ordinary vampire bats, favoring old buildings that allow egress in either bat or human form. It can summon these bats to its aid at will, and will hunt together with a group of them in giant bat form.