The Book of Valor
No RPG is complete without a nice bestiary. Even though the rulebook contains notes on critters from present day Britannia (after the ascencion of the Avatar), a more complete historical version was compiled to give gamemasters the opportunity to incorporate creatures from different realms or timeperiods into their gameplay and also place them in accordance with canonical lore.
As such I present Quill Dragon's Historical Bestiary of Britannia. May the number of critters that slay you always be less than one (or if that doesn't work out, have a resurrection spell handy!)