Dire Rats with some SLAs and speech.
Non-sentient.
This reminds me of a very entertaining touch that my old GM threw into a dungeon. Awakened maggots! He basically just used dire maggots (Small sized) and gave them minimal intelligence so they could speak. The maggots had very energetic personalities and acted as if they were already agile, swift flies, not quite aware that they were a bloated worm-like thing. Much like the penguins in
Madagascar.
GM: As the maggots inch away slowly they cry things like, "Flee my brothers!" "Flee, yes flee!!" "For the shadows, brothers!" "What are the strange, flickering bright things they hold?"
Druid: Can I try animal empathy to get them to help us out? I bet they know this place well.
GM: Sure... (later) Yes, they seem to want to help you out. "May we burrow into the large one's innards?"
Monk: "No, I'm afraid he'll need his innards. Maybe you can help us find someone else his size that also still needs his innards."
GM: "Ho, but we are the only ones here who need your large friend's innards!" "Yes, it would be warm in there!" "Brothers, charge! We will feast on his warm innards!" The maggots start to slowly turn toward the half-orc and start to crawl in that direction.
Fighter: "No, I think what he means is..."
Cleric: "Stop trying. Maggots! Show us how to get through this wall and we will give you a corpse to burrow in and feast on!"
GM: "Brothers, I have a plan!" "What is it brother? We drain them of fluids and dance like mosquitos?" "No, we let these lumbering beasts find us a meal!" "Yes brother! This is a safer plan than charging." "We will show you our tunnel, beasts!" "Kill us something large and meaty, foolish servants!" The maggots start to slowly turn toward the wall and crawl back into the shadows.
So anyway, steal this if you care to. It'll make for a fun alternative way to get XP.