One of those days

Okay. I was thinking about this classic PSX game "Nightmare Creatures" the other day. This is a beast from said game that used to punk me pretty hard when I played it, and it fits in perfectly with an idea I had for the Spoils of Annwn:

THAMES MONSTER

This is usually as far as I got.

No. Appearing: 1
Alignment: C
Move: swim 60' (20')
Armour Class: 17
Hit Dice: 8+
Attacks: 5
Damage: 1d6x4/1d10
Save: Dwarf
Morale: 10
Hoard Class: XIX
Experience: 1560+

One of the many varieties of fiends that haunt the ruins of Londinium, the Thames Monsters make travelling by boat in the area a risky proposition. Lairing in any water deep enough to hide in, they have polluted the rivers of that cursed city with salt and slime. 

Nobody has seen the entire body of one of these beasts. The only parts that rise above the water are a giant serpentine head with a gaping toothy maw, and four long tentacles that pull victims in to be devoured. Normally the head is about the size of a human torso, and the tentacles can stretch about 50'. Larger varieties of these monsters do exist, though. The giant that lives in the Thames itself (15 HD) and is the namesake of its smaller cousins is rumoured to have tentacles snaking hundreds of feet down the streets near the river, feeling for prey.

The Thames Monster waits for prey to come close, and then reaches its tentacles out to seize it. Victims may not even see its head until it's too late! It can attack up to five times per round: four with tentacles and one bite if any being is close enough to eat. NOTE: grappling sucks. We all know this. What I would do is just have a tentacle pull the victim 10' towards the monster's mouth on a successful attack. If you are feeling especially merciful, or the particular Thames Monster is a weak or small one, maybe the tentacle deals damage OR it pulls its victim closer, but not both. The tentacles have the same AC as the Thames Monster itself, and will be crippled/severed if they take damage equal to 1/4 of the monster's total HP. If all its tentacles are damaged and it doesn't have anyone in range to bite, it will retreat beneath the water. If it isn't killed, its tentacles will re-grow at the rate of one every 1d6 days.

Like other unintelligent fiends from the outer reaches of existence, the Thames Monster is indifferent to treasure. The undigested parts of its victims, along with the cargo of boats it has sunk, will litter the muck of the riverbed all around it. In addition to its listed Hoard Class, you might want to add some equipment from dead travellers/adventurers: mildly chewed suits of armour, weapons, magic items, whatever. More victims would lie on the riverbed beneath bigger Thames Monsters.

WOLFBATS

Last night I discovered that He-Man is on Netflix. Digging deep into that bottomless pit of lunacy revealed these, just as I was looking for more ways to punish players for even showing up to game day:

You IDIOTS!

No. Encountered: 1d20 (1d100)

Alignment: N

Movement: fly 150' (50')

Armor Class: 14

Hit Dice: 1d3 hp

Attacks: 1

Damage: 1d4

Save: Fighter

Morale: 7

XP: 7

Similar to garden-variety bats, except with the slavering heads of wolves. You heard right. From a distance they sound indistinguishable from a huge wolf pack, which should be properly disconcerting to any adventuring party (especially in the dungeon). With their vicious wolf-bite, the only reason we don't call them "Sir" is their cowardly nature. 

When a battle is first joined, before any Wolfbat has been slain, they will swarm around their victims and try to distract and terrify them into fleeing or submitting (anyone in a swarm of 10+ wolfbats is at -2 to attack rolls and saves, and spellcasting is impossible) just like regular bats do in the Labyrinth Lord book. Except unlike regular bats, they follow this up by biting your face off. When one of their number has been slain, they make morale checks every round until they fly away in fear. Thus it's tough to eliminate a pack of these things completely. Keep track of how many Wolfbats are left, and the same number will come back if you roll them on the encounter table again on the same dungeon level. 

Now play this monster jam the next time your players feel the slimy tug of a tentacle around the ankle: