A Lazy Sequence

Introducing Manticore

26 August 2014

Manticore is a web app for the 13th Age roleplaying game that streamlines the process of creating balanced encounters.

It implements the rules for Building Battles on page 186 of the 13th Age core rulebook, in particular the pricing table. This application will automatically produce a set of all – within reasoni – encounter combinations that are allowed for a given party and selection of monsters.

Manticore is not random and it is exhaustive. You simply specify the party size and level, and some simple filters for the bestiary and click Generate encounters.

For instance, a selecting a party of four first level characters with the roles troop and archer, and the Tags skeleton will generate 4 encounters:

  • Skeletal archer ×1, Blackamber skeletal legionnaire ×1
  • Skeletal archer ×1, Skeletal warrior ×2
  • Skeletal archer ×2, Skeletal warrior ×1
  • Skeletal archer ×4

In addition to saving you having to do some math, you may find encounter combinations that you would not have considered if you had to put them together yourself, and that spark an idea.

Hopefully the tool is useful to you in your games. Bug reports and feature requests are welcome.

The project is on GitHub. Please feel free to report issues there, or make pull requests. The most pressing feature is content: I only have the core rulebook at this time, so I have not been able to provide entries for creates from the Bestiary or 13 True Ways.

You are more than welcome to run your own copy of Manticore. The only requirement is a web server. The program runs entirely client side. It does need to be accessed over http(s) due to performing ajax requests to pull down bestiary data. Building the latest from git requires a basic unix (Mac OS X or linux should be fine) system with make and TypeScript installed (probably via npm) Alternatively irregular releases will be made available via the projects GitHub releases page.

Running your own instance will allow you to add campaign specific entries in the optional custom dataset (found in static/data/custom.json – just create it if it does not exist already).


  1. Running the search against the full dataset of monsters for four first level characters can easily run for 20 minutes. for higher level characters where there are options both in the levels below as well as above things can run much longer. As a result the program clamps the computation to two seconds. Hundreds of thousands of results are of no use to anybody. You are better off refining your search space.

13th Age character creation

12 August 2014

My weekly gaming group has begun playing 13th Age. As with most games the first session was devoted to character creation. Prior to this session I had created a few characters (including porting one from Pathfinder) to get a handle on the process.

With character creation spread across four chapters of the book there is a fair bit of page flipping. I have yet to internalise the process, but the simplicity of characters (for a d20 fantasy game) means that the checklist on page 29 and character sheet are sufficient for guiding creation.

In 13th Age characters are described with a mix of traditional crunchy bits and also mechanised fluff. I have found I like to alternate between the two kinds of content as I generate the character. When working out crunch, my brain can process fluff in the background and vice versa. This back-and-forth has proved to be an effective feedback cycle.

I have enjoyed how easily I can simply start building a character with no concept, quickly lift an idea from an example somewhere in the book, and without any specific thought, the activity of filling out the character sheet has pushed that idea into something I would not have created myself. No analysis paralysis, no worries about clichéd (or anti-clichéd) characters.

Without getting too “Let me tell you about my character…”, an example. At this weeks session I decided that I would play a gnome sorcerer, but beyond that I had no concept. While trying to figure out why the character would choose a poor ranged weapon (throwing daggers) and a moderate melée weapon (a spear) when the stats suggest he shouldn’t ever get into melée, I read some of the sorcerer class overview: “…If your sorcerer was cursed at birth to wield the power of the Lich King…” (pg 132). It was obvious that a gnome (gnomes live underground) with an inappropriate weapon would have stolen it from a crypt of the Lich King, and that the weapon was cursed. That provided both the one unique thing for my character and all the direction I needed.

I have been impressed with the careful balance between providing detail and ideas and leaving the setting open that the text achieves.

On the mechanised fluff:

The one unique thing rule is great. I found that creating a couple of different characters and coming up with multiple uniques for them was an important exercise for getting the hang of them. The rules provide a lot of examples and discussion so creating my own and then comparing them to the discussions was helpful for getting a good grasp on these.

Backgrounds are a cool skill system. I like the concept but they have proved to be the most difficult aspect of character creation for me. I think this is one aspect of having a less specified setting can be a challenge for new players. Perhaps this will become easier with more experience with the system and setting, or with additional material in 13 True Ways?