Its grid based in exactly the same way Diablo was. In fact, its a bit of a spoof off of diablo... the last couple levels are a little *interesting*. So its not very apparent, but the entire thing IS actually taking place on a grid; every 64 pixels you move in each direction, the entire screen is refreshed and all the tiles reload their animations, ect ect. So as far as the game is concerned, everything takes place on a 128x64 grid, lol.
I might end up posting it open source, just since my coding was particulary awesome on this; I'm making the entire thing in TGF, without any scrolling and without ever changing frames.
I need to come up with a better explanation of "Grid based" games it seems. Pixelthief, your game doesn't qualify as it stands right now. Now, if you made it like Fallout (Non "free" movement) it would.
You said it played like diablo, which doesn't fit into the "grid based games" theme. The map was certainly Grid based, but the game and movement was not. As a general rule, your character must be locked into a cell while not "transitioning" to another cell.
Basically, if I hit up, the character should move to the next cell up; no stopping "in-between" cells etc.