Bifrost originally surfaced in the late 1970's / early 1980's and appeared in 4 Volumes. Here you will find scans of the original rules. Over a period of time more material will be posted here adding to and explaining how these work and how to utilise them to create role playing scenarios and entire worlds within which to enact them. First here are some links that will introduce you to the first volume "Faerie".

Bifrost Volume 1 - Cover, Acks, Intro, Setting Up Game  Bifrost Volume 1 - Game Content, Seq Actions, Choice of Char, Trg, Indiv Abilities  Bifrost Volume 1 - Alignment, Gods etc Bifrost Volume 1 - Social Pos, Prices & Equip, Maps etc, Campaign Surv, Fatigue Bifrost Volume 1 - Disease & Illness (inc Wounds)  Bifrost Volume 1 - -Tables - Incident Type Loc'n, Area Type & Creature Group Civ & Unciv  Bifrost Volume 1 - Tables - Creature Group Wild  Bifrost Volume 1 - Tables - Incidents Men, Human Group Civ, Unciv, Wild, Characteristics  Bifrost Volume 1 - Morale & Reacts, Weather, Playsheet, Progression & Advancement  As you will no doubt have surmised these are complicated and are not complete without further rules. Fighting is a key activity in any fantasy RPG of this kind. The second volume "Combat" introduced the game's basic mechanisms for determining the outcome of combat. Here are some links that will provide you with these:

Bifrost Volume 2 Part 1 Bifrost Volume 2 Part 2 Bifrost Volume 2 Part 3 Bifrost Volume 2 Part 4 Bifrost Volume 2 Part 5 Bifrost Volume 2 Part 6

Volume 3 dealt with Magic. There is a post (Here) dealing with this (and a link to a pdf of the rules which you will need to download due to its size.) Volume 4 expanded upon the original 3 volumes and it was written by a different group of players (of whom I was one). It provided complete lists of all the characteristics of the creatures in the creature description tables (see Vol 1) together with additional combat rules and handy sheets to use when creating characters and some play sheets summarising the rules for ease of reference during play. The additional rules included unarmed, mounted & aerial combat, combat fatigue, health of horses, primitive firearms, literacy and optional combat amendments. In some ways most importantly there were some basic guidelines as to how to play the game and hints regarding the use of magical artefacts to help provide structure and options for plot development during campaigns. Here are some links to these: Bifrost Vol 4 - Intro - Playing The Game  Bifrost Vol 4 - Additional Combat - Literacy etc  Bifrost Vol 4 - Creature Description Tables - Character & Play Sheets 

So Vol 4 delivered most of what had been promised plus more. There were still some gaps however that were never published in any form and as a result of several years play - that would eventually yield a novelised version of a longstanding campaign - masses of notes and ideas for expansion and improvements to the rules were created and would then languish for thirty years. The additional Bifrost material referred to above will be made available in due course, including all the written material that we used to create the world that our campaign took place within.  Bifrost is a complex rule system that would benefit from being "automated" in ways that either were not possible or were extremely difficult to achieve back then - but which are now fairly straightforward. We will explore this in future posts. The ultimate aim of this "project" is to recreate and revitalise Bifrost so that it can take its rightful place in the pantheon of RPG systems enabling future generations to explore and expand upon its many possibilities.