Campaign help, bounties and bad guy D&D 3.5

[Ya boy J-roc]

I am the DM for a party of 6 currently at level 4. They are a group of mercenaries/ bounty hunters so any good bounty ideas would be awesome. They saved a town from a goblin attack. As they entered the last room of the encounter they witnessed a gaseous form escape through a window. I haven't decided who or what I want the big bad guy to be, so I put a gaseous form pot on one of the geared hobgoblins. (I'm thinking a demon, vampire or lich.) I want to have them continue to complete bounties that will lead them to this evil creature's plot. Any ideas would be appreciated.

[Ya boy J-roc]

Wow thanks. I'm not so sure about the bugbear vampire cleric but I like the goblins being an expendable pawn to test the defenses. I already had them clear rats out of the sewers where they found a small band of goblins that led them to the goblin attack on the nearby mining town. I like the idea of vampire spawn leading bandits and bands of other humanoids. I was going to have the party return to that town for a tournament, I could have the leader be turned into a vampire when they return. Should be interesting.

[Ya boy J-roc]

Ok I like the bugbear that makes way more sense now. I think I'll have him be the one hiring bandits and arranging kidnapings.
Edit: I could have the bugbear be a reincarnated follower of the vampire and have more reincarnated followers in he other towns!

[Scorponok]

I think you could add interesting elements to these just via the environment.

Say, have a bounty for someone who kidnapped a town counsellor's daughter, and is holding them in a farmhouse near a stream that has guards guarding the bridge. Attached to the house is a water wheel that the PCs can jump and hang on to, giving them a quick way up to the rooftop, where they can slid down the chimney to avoid the locked door. Stuff like that.

I probably have more to contribute so I'm replying to this now just so I have a post marker.