A couple of months ago I posted the Ultimate Grand Unified Junk Table, the most complete random junk table (that I know of) for post-apocalyptic games like Gamma World. At the time I considered something similar for a massive table of random mutations. Now, thanks to The Metamorphica, and its author Johnstone Metzger, I don’t have to.
The Metamorphica is broken down into two parts: the first part has tables for hundreds (maybe thousands?) of mutations with brief non-mechanical descriptions, and the second part has tables for generating mutant characters in various settings, such as post-apocalypse, super-heroes, grim fantasy or sci-fi.
The mutations come with no rules or mechanics. This is great if you’re using a relatively rules light system. But if you’re using a system with some crunch (like Pathfinder, for example), you’ll have to do some work. Still, it’s a marvelous reference source and compilation of various mutations drawn from a wide range of material, and you can always just pick and choose the ones you like best for your game.