Dungeons of Dredmor is a graphically upgraded "roguelike", a classic genre of dungeon-crawling RPGs that are usually represented through ASCII characters. While the actual "game" parts are less developed than many of its contemporaries, Dungeons of Dredmor is in a lot of ways more accessible to the common gamer than most of its counterparts.
Dungeons of Dredmor has a fairly simple premise. You are an adventurer, loaded up with 7 skills (ranging from weapon usage to trap-finding to spellcasting of various flavors). Your job is to get as far as you can into Dredmor's Dungeon while getting as much gold and loot as possible. Unlike traditional games, roguelikes like DoD aren't really meant to be "beaten", but rather it's a test to see how far you can get. The dungeon is random every time, and contains traps, monsters, treasure, and various sundry shrines and merchants. This means that the experience is new every time, and while it also means that the dungeon is pretty much laid out as though a lunatic made it, it makes up for it with new content.
Like other roguelikes, DoD is a semi turn-based-game. In essence, every time the player moves, so does the rest of the world. You can stand still and nothing will happen, but if you move, attack, or choose to wait, all the monsters will move/attack/whatever. This means that it's possible to pause and plan, but it also keeps the pressure on the player since there's only so much that can be meaningfully done in a given period of time. While it may be a bit hard for a new player to understand, DoD's graphics at least make it easier to see what's happening.
Interaction with the world is generally based on trial and error. Exploration and discovery are the game's main focal points, and thus the ability to adapt to new information is key. There's several crafting systems, allowing the player to make new weapons, armor, gadgets, and even traps. Through various tasks (including killing monsters, disarming traps, and unlocking doors), the player-character gains experience that can be used to upgrade the seven skills chosen at the start of the game. It's a pretty solid mix of different choices that are still relatively useful, and experimenting with different abilities is part of the game's fun.
The real issue with DoD is that, as a roguelike, it's not that great. "Graphics" and "presentation" are really all it has going for it, and while that may matter to some players, others will be less influenced by that. It's a good introductory Roguelike to help casual players understand the concept, but in terms of actual material it's not that great. The graphics are nice, but they hardly carry the game on its own. However, for only $5, you could do a lot worse.
We purchased this game with our own funds via Steam.