Mayfair Exponential Game System

The Mayfair Exponential Game System or MEGS is a rules system developed for role-playing games. The name was what fans called the game system for DC Heroes, which was later used for Underground (1993). It is noteworthy for its use of an exponential system for measuring nearly everything in the game. This system makes it possible to have both cosmically-powered characters and ordinary human characters meaningfully interact within the same universe. For example, in DC Heroes, the first game to use MEGS, Superman's strength is several orders of magnitude more than Batman's. With the MEGS system, however, this large difference in strength is scaled down. So, while Superman would still have a clear advantage in a brawl, Batman is at least able to hold out for a while, mirroring how superhero combat often operates in comic books.

MEGS was originally developed for the company Mayfair Games for the modern superhero RPG DC Heroes. The system was heavily modified for Mayfair's cyberpunk war veteran RPG Underground. The original incarnation of Pulsar Games licensed MEGS from Mayfair Games and used it in their modern superhero RPG Blood of Heroes. Blood of Heroes is very similar to DC Heroes, mostly replacing the superheroes created by DC Comics with new ones for the Blood of Heroes universe.

The core idea in MEGS is that all measurements are done using a logarithmic scale. The units on this scale are called "Attribute Points" or "APs" in the superhero games and simply "Units" in Underground, with each unit on the scale represents exponentially increasing values for length, weight, time, etc. Because of the nature of logarithms and exponents, 0 APs/Units is a meaningful, positive value. Indeed, even negative APs/Units still represent positive values, though exponentially smaller, down to -100 APs, which is defined as absolute zero for all units.

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