The Black Omen: Warriors of Prophesy
paint their 'Mechs black and now trim them with blood red highlights.
Per FM: Merc, page 38.
Tarantula, FM: Mercenaries (plate 12)
The unit insignia, a spread-winged raven set over a field dripping with red, is placed on the upper left torso. Per FM: Mercenaries Supplemental II, page 24.