The Abyss-class Battleships were a triumvirate of unique Imperial Battleships of special configuration secretly constructed for the Word Bearers Legion by a Dark Mechanicum faction of the Mechanicum in the days just before the outbreak of the Horus Heresy in the early 31st Millennium. The Furious Abyss, the first ship of its class, was created and built in the Jovian shipyards of Thule which orbited the gas giant of Jupiter in the Sol System in the early 31st Millennium. Its sister ships, the Blessed Lady and the Trisagion, were constructed at the same time in an undisclosed location. These vessels were constructed in secret during the latter years of the Great Crusade by the Renegade Mechanicum faction loyal to Kelbor-Hal, the traitorous Fabricator-General of Mars' Mechanicum. These vesse