In the spirit of a 2009 7drl post, here are some ideas for your seven day roguelikes. I will continue to update this list as I get more ideas. Have fun:
Army roguelike – Instead of being a single @, you are the commander of an army. Instead of hp, you have masses of recruits, and attacking (either with the melee force of your army or using ranged troops to engage from a distance), causes casualties instead of lost hp. Find recruits, and drive back enemy armies to achieve victory!
Bunny roguelike – You are a rabbit, trained in the ancient art of bun fu. Fight the foxes, dogs, and other predators that are attacking your hole. The boss is the determined human exterminator who came to flush out the rabbit extermination.
Escape the light - http://www.youtube.com/watch?v=L7a8hmoOsx0
You cannot survive in the light, so run right as fast as you can. Killing monsters and using items will give you a boost of speed to endure. How long can you last?
Evil Overlord Roguelike – A horde of adventurers are attacking. To stop them from coming, place towers that shoot ranged attacks, camps that house attacking monsters, and traps. Come out personally to deal with the invaders and collect their treasure, but if you die, it takes time to respawn.
Immobile wizard roguelike – You are a wizard rooted to the spot. Blast the legions of foes coming to kill you!
Invulnerability roguelike – You are immune to death. However, you still have a food clock. Enemies will try (ineffectively) to kill you, but they may try to prevent you from getting your food…
Internet Meme Roguelike – Make a roguelike based off of internet memes/characters (but it cannot be for mature audiances only please)! You could play as Nyan Cat, or Annoying Orange, or Hatsune Miku. Items could be a Three Wolf Moon T-Shirt, Noms, or cake (but its a lie!). Enemies could be Trollface, animals that are really Nope! Chuck Testa!. The adventure could take place at candy mountain…
Parallel Universe Roguelike – You have multiple copies of yourself, existing on different z planes but always the same x and y of a dungeon that may or may not be similar. Be careful, as you can only move or attack if none of your doubles can bump into a wall, and damage is shared among your parallel selves.
Philosophy RPG – A roguelike where everything is a reference to something philosophical. For instance, the dungeon is plato’s cave. You attack with the four Aristotelian elements. Enemies could be nihilists or something.
The following is a good source of ideas:
Positive/negetive energy roguelike – You have a positive/negetive energy bar. Casting spells of the appropriate element will bias the bar towards that element, and make those spells more powerful, while reducing in power spells of the opposite element. Positive energy spells provide effective healing and protection spells, while negative energy spells provide powerful offensive attacks. Be careful, as getting too far in either element will spell the death of your character. A food clock and mana bar will balance this mechanic.
Possessor Roguelike – You are a lost soul, aiming to get to the bottom of a dungeon into the next life. However, you can only hitch temporarily on recently deceased creatures. Kill creatures, and you can slip under that creature’s skin. This is like a disguise, some monsters will ignore it, but some may attack you on sight, so be careful!
Potion mixing roguelike – potions, when drunk, will have a temporary effect. If you drink another while the effect of one is still going, a random positive or negative effect happens, sort of like nethack’s fountains. It may be lethal, or both effects could cancel, or one of the effects could be permanent! Ideas for effects: http://www.wizards.com/default.asp?x=dnd/dnd/20060401b
Warped time roguelike – While your movement is turn by turn, enemies will move in real-time. You can take turns quickly in desperation, but doing so will deplete your Energy bar, and if it reaches 0, game over.
Weapon Stacking Roguelike – As you level up, you gain access to “connectors” that allow you to stack your weaponry, which means that each weapon on the stack can attack simultaneously. Make insane weapon combinations to defeat the monsters. You can also have armor stacking for an extremely silly roguelike.