Bill the Demon
Originally created for the Macintosh (System 7) back in 1996, Bill the Demon is an action adventure platformer with a very nice old-school flair to it. This version was recreated in Flash by the author, James Burton, following Apple's decision to stop supporting older applications.
In the game you play as Bill, a lowly demon with a voracious appetite for human souls. To prove himself worthy to his peers, Bill sets out on a mission to the Ninth Circle of Hell to fetch the devil's autograph.
Use the keyboard for control: [left] and [right] arrows, [up] to jump. Press [space] to scream. A scream is important as it will allow you to eat a human soul (if close enough), and it will also break down some walls and stun some monsters temporarily. Alternatively, you may use the [A] and [D] keys for left and right, [W] to jump, and [shift] to scream. Suit yourself.
As you move about each circle, Bill's hunger will increase. Eat souls wisely as they will help you move deeper into hell. If Bill gets too hungry, you will lose a life and have to start back from the last checkpoint you reached. Lose all your lives and you'll have to restart the game from the beginning. Luckily, once you complete each circle you will be given a passcode with which to load the game from there.
Analysis: Bill the Demon is a great game that is a lot of fun. It certainly brings back memories of the old 8-bit scrolling platformers. The levels have been designed well and they present a challenge that will keep you entertained for hours. There really isn't much to dislike about the game other than the being set back from time to time when dying or running out of lives. Still, for anyone with even a remote interest in old-school platformers, or in demon-themed games to get into the Halloween spirit, you could do much worse than this charming little game.
Cheers to Bob and Mango for suggesting Bill. =)