Reading a pdf I bought recently (Brixbrix's Fieldguide to the Creatures of Ados) and found a few new critters to add to my favorites list-
The loadstone golem is unaffected by metal weapons (huge DR) and acts as a magnet...
The coral dragon (written up as a true dragon) looks like a leafy dragon (those fish that look like leafy seahorses) and has a nasty BW and poison stinger (both have the same DCs and damage). It fills a niche for a totally aquatic dragon for oceans and seas.
Sejteocin is undead wood (with spells to animate it). Any wood- chairs, logs, twigs, houses. It is written up like vermin (size=stats). Now haunted forests can be on the move