Anguna is a homebrew game for Gameboy Advance and Nintendo DS, featuring art by Chris Hildenbrand. It was released in 2008, and now is available for a short time in cartridge form by Piko Interactive.
5 dungeons and a large overworld to explore
Multiple weapons and items including: a sword, bow & arrows, bear traps, dynamite, lantern, magic boots, and more
Many hidden rooms, secrets, and powerups
Lots of interesting enemies and boss monsters
There have been various ports or attempts at ports of Anguna over the years:
GBA: The original Anguna, finished in early 2008
DS: Thanks to hardware donations from Tim Dudek and Electrobee, this was finished in December 2008
Sega Master System: Sverx (who made the audio libary used in the NDS port) has been working on an attempted port of Anguna to the Master System. It looks like the machine doesn't have quite the power for the nearly direct port that he hoped for, but the game has been entered into a SMS Homebrew Competition.
Genesis: I'm been giving some advice to a fellow who was interested in porting to Genesis. Hopefully it will happen eventually!