The Fathomless Mastery is the third full length album by the Swedish death metal band Bloodbath. It is the first full length Bloodbath release to feature the new guitarist Per "Sodomizer" Eriksson. Former Scar Symmetry vocalist Christian Älvestam did guest vocals on the sixth track, "Iesous". The outro of the final track, "Wretched Human Mirror", features samples from the movie I Am Legend. A video was made for "Hades Rising". The album appeared at #45 on the Heatseekers Chart.