Maybe I should be a little more specific on this, though...
I mean pseudo-sentient that
behave differently. The purpose is to have creatures with bizarre goals or behaviors.
Domovoi, which are spirits of domesticity, functionally, and are beneficial to families that can manage to keep one in the house, even though it looks like a cross between a wizened old man and a yeti is a good example of this.
Miner bees, which are real-life creatures, and hence, not pseudo-sentient monsters at all.
The firebirds are just creatures with different kinds of bodies, but you aren't explaining anything different in how they actually behave.
The multi-tile monster sounds most like being a living weapon trap, which is an interesting concept, but these things are not really the purpose of this thread.
Like the domovoi, these don't all have to be necessarily hostile. Or at least, not
directly hostile.
In other words, this:
I'd like to see some things more akin to traditional Gaelic and some Brythonic faeries. They were often not so much outright malicious (though they often could be) so much as possessed of a very warped sense of ethics that lacked the remotest sense of empathy for others. And a lot of them just looked weird. There's a Scottish creature that had a head the size of a whale on a man's body, with translucent skin and an enormous grin. He'd wander up on beaches sometimes and consume people with his massive maw. In one story, a priest gets it to stop by offering him hospitality (he gave him a cask of wine), and asked why it did such awful things. "I'm hungry." Then it went back into the sea. Some are pretty nebulous creatures, too. Like a kind of giant hairy man in some Manx and Scottish myths is seen, sometimes, but disappears into fog, and leaves a person with a sense of unnatural dread that drives a person mad with terror, often to the point of suicide. Hill-women were some kind of vampire like being that moved in groups. One would convince a lone traveler they needed assistance. If they followed, they'd be torn limb from limb by the rest of the group and their blood consumed from the wounds, and the creatures were revealed to be the dessicated phantoms of deceased women. I use these specific examples because they all had the same severe weakness to worked iron. Touching it would cause them to die. I find it funny because it's such a plain metal. I'd like some very bizarre, dangerous, or just gross things that could die by such bizarrely simple means (given, at least in said cultures, iron wasn't exceedingly hard to come by; considering the Gaels' view of how their people came to be, with invading Ireland and all with superior weapons, it was probably just a commentary on that, but it still lead to some hilarious and weird myths).
I'd really like to see catacombs and such offering creatures specific to the cultures that built them. Think of a civilization resembling the old Norse peoples; tombs could sometimes be guarded by something akin to a draugr in certain cases. But similar beings don't exist in all other mythologies. It'd be a good chance for some dynamism culturally, giving a region more direct character in relationship to the peoples who live in it. It'd really be nice when cultures are themselves more dynamic.
You might also want to take a peak at White Wolf's "Changeling" games... Ogres are creatures that typically like eating human flesh and grinding bones to make their bread the more "fae", and less "human" they become, but even then, they are creatures you can actually talk to and bargain with... so long as you can offer them something they want more than eating your flesh.
Others, like Fairest, have supernatural powers of manipulation and beauty, and just enjoy ruining people's lives through mind control for the sheer shits and giggles of the power trip.