Old School: 13th Age and a Megadungeon

13th Age OSR?

Recently I picked up 13th Age, and have been playing a lot of it. Like most of the games I have been playing lately, it is very light on the rules and lends itself to some good gonzo action. There are numerous reviews of 13th Age out there, so I wont reiterate what has already been said better by others, I will just state that the game has a very dear place in my heart now.

So of course I want to see what it can do with it. Thus far my games have been in the Dragon Empire (the default setting for 13th Age) with very little customization other than adventure locations. I think it's time to take it a step further and try to bend it.

I'd like to make it more OSR-like. I'm not proposing some major system overhauls, just a few house rules and mainly a change in the way magic items work in order to get that old school adventure feel. I'd also like to throw the characters into a Megadungeon so Rappan Athuk will be serving as the setting for this experiment.

OSR Houserules

The following are a list of house rules I am working on to make 13th Age more OSR-like.

Delving Deeper

Leveling in 13th Age is usually based on DM fiat, but I want to encourage risk vs reward which is a classic archetype of OSR games. I am looking at advancement as a combination of treasure recovered and returned to town, as well as depth the troupe has reached. An idea:

• X amount of treasure returned grants an incremental advancement.
• Major encounters defeated grant an incremental advancements.
• New level delved grants an incremental advancement. This only works for "true levels" not sub-levels.
• Thoroughly exploring a level grants an incremental advancement. (maybe for sub-levels)
• Every 4th incremental is a level.
• Replacement PCs will come in at a level based on depth attained by the party. (2nd level PCs come in on level 3, 3rd level PCs come in on level 6, etc.)

I may have to slow this as they continue to descend, and will be tweaking it probably before we run the adventure. Right now I'm figuring every 3rd true level would be worth a level. Possibly quicker at the top, and slower at the bottom.

Magic Items

In OSR type games, magic items tend to be rare, consumables a little more powerful. 13th Age magic items are potent but not campaign altering. 

• Scrolls will function with 13th age versions of spells.
• Not all magic items are created equal. Though I will stick to the 13th Age magical "pluses" some magic items will be stronger than others - A sword of speed might give an additional attack on an even roll, once per round. A vorpal could sever a head on a natural 20.
• Wands will most likely function once per battle, no recharge roll required, and run out after x charges.
• Wands, Scrolls will not count toward major item limit, unless the wand is a true implement.
• Cursed items - need to be nasty.
• 
  

Danger Level / Sandbox

Rapp Athuk is a dangerous place and I will have the danger levels of the encounters be set based on the dungeon level / challenge of the room. Characters may very well run into things they cannot handle and will need to flee.

Full Rest

A full rest will only be available in town, unless they find a truly safe area that allows them to rest in the dungeon. They will want to return to the town with major money hauls for their incremental advancements, anyway.

Icons

Icons play an important role in 13th Age and I'd like them to take a role in the megadungeon, however the story of the megadungeon is exploration and danger, not so much one icon opposing another. So, I am thinking of the following house rules:

Icon benefits (5's or 6's) can be exchanged for a few different things during the course of a session. It will be up to the player to make sure they get use out of their benefits.

• 5's: Must be used in town. 6's can be used anywhere.
• Identify: Your relationship with an icon allows you to identify a magical item you find, and figure out it's command words. Maybe a strange piece of lore or a poem you were told.
• Clues: The GM can give you clues to solve a riddle, a trap, or locate a secret door.
• Escape: You can spend an icon relationship benefit to escape from a dangerous situation. 5's can be used to escape, but will cost you 2 recoveries to do so.
• Healing potion: In town you can gain a healing potion, magic oil or rune.
• Monster Info: Some monsters require special conditions to harm or have dangerous abilities, an icon relationship can give you that bit of info you need.