The Holy Shotgun also referred to as the Demon's Bane was an iconic weapon that made it's debut in The Battle of Deroth saga it was primarily used by Ramasus Ei Valinus after obtaining it from the unorthodox physical hologram Buddy. It was used to dispatch of the demonic entities that plagued Deroth, and the world's inhabitants whose biology was tainted due to Lucifer's sheer power.
The weapon was later abandoned by Ramasus shortly after his battle with The Learner and acquired by Eurybus who used it at the beginning of the Rise of Evil story arc that featured the return of Eurybus. He later dropped the weapon after meeting up with The Alliance-- it's fate is unknown presumably destroyed after the universe was reconstructed.
The weapon was relatively technologically advanced; of an unknown construct. It shot powerful shells that were carved with religious symbols that held great supernatural power over demons and the like. It also held three lights at the top of the gun which proved to be a huge advantage for Ramasus who used it to navigate the dark world of Deroth. It was gold in design.