Description:
Down below the streets of New York City, there exists a world of wonder and adventure, unseen by those above. Magic courses like blood through veins made from steel tracks and transformers. The UnderWorld is home to the Homeless, to the Freaks, to the Junkmen and more. Steely-eyed Bravos hunt their prey in dark tunnels far below the subways, while brave Taggers scout new paths between the varied Domains, and mark trails for all to follow. Creatures of Legend walk the platforms below the city, and brilliant Artificers build inventions of bizarre science, borne of madness.
This is a world of heroes and villains...
of magic and romance...
of gods and monsters.
Unseen. Unknown. Unforgettable.

UnderWorld is an adventure game, usable for either table-top or live-action play. All you need are the guidelines presented in this book, and a handful of coins.
In 1999, game designer Gareth-Michael Skarka let gamers witness the design of an RPG from the beginning, via a column on RPGnet. The game, UnderWorld, was released in 2000 to critical acclaim, and sold out quickly. Now it is available again, in PDF via DTRPG. Read reviews of
UnderWorld:
Read the original design column, Game Design Step by Step, at RPGnet