The original game saw the player running around a grid, gradually uncovering the pyramid's secrets. Each time the player's path entirely surrounds one of the rectangular blocks it reveals its contents. This can range from more enemies, who will follow the player to the next level, to defensive scrolls that protect the player from harm and items required to unlock the next stage. The new version not only adds redrawn sprites but also a number of variants, such as an invisible level where only the player's and the mummies' eyes are visible, which shows an inventiveness that bodes well for the full release.
1985Alternivo are taking pre-orders from international buyers in the run up to this October's launch date and they offer extremely reasonable pricing, from the looks of things they're selling pretty much at cost. So if you own a Mega Drive and are interested in checking out what could be some great fast-paced arcade action why not check it out.
Do note that currently international buyers are asked to e-mail the team directly, contact details can be found in the link above.