Sometimes carving out a hole in the wall may lead to a new path or unearth valuable items. (Forget the barrels and chests cliche.) The heroes will find increasingly devastating and spectacular ways to purge the evil in the forms of new abilities and weapons, or even create their own arsenal by combining the existing ones.
Circle of Doom also delivers a complex and twisted story plot in a very different and new way. However, players are not forced to understand and follow the story. Even during a multiplayer game, one player's choice to stick with the plot will not slow the others from journeying onward.