lake slaver

No. Enc.: 1 (1d4 in lair)
Alignment: Chaotic
Movement: 30' (10')
Swim: 120' (40')
Armor Class: 6
Hit Dice: 6d8
Attacks: 2 (tentacle lashes) or spell.
Damage: 1d6/1d6 or spell.
Save: M3
Morale: 6
Hoard Class: VIII + XII

These strange, aquatic creatures resemble an octopus with human mouth and four fanged tentacles sprouting six-foot long from a bulbous body the size of a bear.  They live in freshwater lakes, rarely venturing out unless food is scarce.  The creature itself can defend itself by lashing out with it's tentacles but only two can attack at any time.  They know a little magic, being able to cast charm person and read magic once a day as a 2nd-level magic-user. They communicate by telepathic speech understood by the recipient.

They spawn every spring, releasing hundreds of fluke -like larvae (AC9, 1 hit point).  These attempt to latch onto passing creatures, often as they sleep.  Animals are slowly killed by the larva draining it's blood (lose 1 hit point per day).  The larva drops off after 6 days and undergoes a chrysalis stage of a week to become an adult lake slaver.  If the creature can speak, the larva secretes a local sedative and burrows under the skin (detect as a secret door).  It also stops growing and undergoes certain changes.  This places the creature under the telepathic control of the parent (as charm person).  This can be broken as per the spell.  Dispel magic (vs. a 6th-level caster) or cure disease will remove an infestation.

The lake slaver will try to control a lakeside community and spawn.  Their innate distrust of each other and parasitic lifecycle limits them though. They lust after scrolls and spellbooks, trying to lure magic-users into being infected so they can 'share their magic'.