This is based off of Dragonfire for the Atari 2600 that was release by Imagic back in 1982. Just like the 2600 version the dragon in the chamber walks back and forth, there is no archer, troll , or moving drawbridge; though I might add the archer in an update, I think the fireballs you have to deal with on the bridge are a enough of a pain.
You can download the scenario to run in the greenfoot editor Greenfoot.org Dragonfire Page
You can check out Dragonfire! from GitHub.
There is also an Executable Jar File you can run. Download Executable Jar and double click; Requires Java 7 to run.