Well, the game below is now tentatively called Labyrinthine. I've got some idea of the basic game mechanics. The game world will consist of an overworld map, on which are various towns and maze entrances. The mazes may be any number of different standard adventuring sites, including caves, dungeons, forests, graveyards, etc. The goal of the game is to collect coins (and other, more substantial treasures) from each site... the coins are needed to buy equipment and weapons, and also serve as the main source of experience points (rather than combat, like most RPGs.)
The game functions like a blend of RPG and arcade game. There's no classes or basic attributes, but lots of skills that can be used to customize your character's abilities. The game uses hit points, but they function more like lives. Each time a monster catches you, you lose 1 HP and you're kicked back to the entrance of the maze (or in some cases, to a prison area deeper within it) and all the coins you've grabbed on that particular raid are returned to their positions. If you run out of HP, you're sent out of the maze to a hospital, far from the action and without any of your gear. Some monsters are also venomous, and if you're injured by them you must seek treatment within a certain time or lose all HP.
You cannot kill a monster permanently, but if you have a weapon you can temporarily incapacitate them. After being hit by a weapon, the monster turns transparent (flashes, actually... this is BYOND, after all) and spins around in place for a short time... the actual amount of time depending on the strength of the weapon and the toughness of the monster. The weakest weapon, a thrown rock, only stuns average monsters for half a second... hardly enough time to run past them, but enough time to run around a corner, maybe. Most weapons can only be used once... combat isn't the focus of the game. Those with the Rock Throwing skill automatically get a small supply of rocks when they enter a maze, and throwing knives are fairly cheap. More substantial weapons are pretty expensive, and should be saved for great need.
The monsters vary in speed, toughness, special abilities (like spiders who litter the maze with webs), and hunting behaviors. Most are not as fast as player characters, and nearly all of them are slower when not specifically chasing somebody, but the maze-like nature of the environment still allows them to trap incautious players.
So far, I've got most of the in-maze portion of the game engine done, and a decent beginning on a stable of monsters (Snakes, Spiders, Bats, Vampire Bats, Kobolds, Orks, and Goblins)... I'm going to start working on the overworld and towns next, and at that point, I should have something very much like a playable game.