Monte Cook's Arcana Evolved is one of the more fascinating fantasy worlds based on the d20 system. Unlike the more generic Dungeons & Dragons 3.x system, the character classes, races, magics, creatures and even the magic items in AE are intricately tied into the world history and themes.
Monsters Evolved: Veiled Denizens continues Cook's tradition. Published by Rite Publishing, the 20 page pdf covers five unique creatures for one's AE campaign. (A print copy can be purchased at Lulu.) As you will see in the following, the supplement is also superbly presented for both traditional fantasy worlds and more exotic ones as well.
The monsters in Veiled Denizens are not your typical creatures for the PCs to slay and get its gold.