I am actually in the midst of GMing a monthly Shadow Chasers campaign right now. As none of my players read these boards, I'll throw out a few of my ideas so far, both used and un-used.
Feedback on any of them would be cool.
The first game was thier introduction to Shadow, so they got jumped by some skateboarding goblin punks. The ruckus they made dispatching the goblins brought the attention of a nearby troll police officer (whom they wisely fled).
Later in the game, they faced some Gnolls after the same articfact as they (at the Rosacrucian Egyptian Museum in San Jose). The gnolls got the artifact, and tracking them to thier lair meant facing thier Fiendish Gnoll leader, more Gnoll bruisers, and two demonic hyenas.
The end of the game introduced an undead knight who showed up, threw a Buik at them, and started advancing on the group. They wisely fled and escaped him as well.
In the second game, the heroes had to solve a rash of dissapearing students. Goblins were being smuggled into our world by an unscupulous mage, who used the dimensional instability of the Bermuda Triangle to "bring them over" into airplanes flying back from Bermuda. (this happened over school vacation, hence the missing students)
The goblins would then follow a randomly selected family home, killing them and "setting up house" where they lived. The mage, meanwhile, ran a travel agency and used Charm Person constantly to sell a ton of trips to Bermuda.
Two final monsters used were the orc bodyguard of the mage, and the dog that guarded the travel agency at night. The dog wasn't a monster, but I gave it glowing red eyes, just to freak the players out.
My next game has them trying to find out why several guys have been injured right before the harvest dance. It turns out that the culprits are dopplegangers (teenaged) who are hard up for dates. They're taking out these dudes so they can show up looking like them, and steal thier dates to the dance.
The best part is, the Player Charatcers get attacked by four Samuel Jacksons holding baseball bats painted purple. As they pull them out, they make really bad lightsaber noises. One of the attack victims is attacked by four Jackie Chans, another by four Scooby Do's. I can't wait! I mean, the bad guys are total dorks, but they're doppleganger dorks. They can be any geek idol they want.
The following game will be my "Halloween themed" game. Unless they can talk thier way out of a frame for murder real fast-like, they will face a crew of creepy circus performers. From there, they will track thier quarry to a real live (dead?) haunted house! It ought to be cool.
Anyway, the thing I love about Shadow Chasers is that monsters are "obscured by Shadow". The creepiest crawly in the Monster Manual (or Menace Manual) becomes a "dude with bad skin" when viewed by the police or a school teacher.