User blog comment:Hyperborean/"The House of Hades" – official expectations blog/@comment-6064271-20130603014353/@comment-10218971-20130603070522

You could keep dangerous monster (e.g. Medusa, Furies, etc) from coming vack from Tartarus if you killed them with Stygian Irron, which doesn't despel them to Tartarus, but instead absorbs them into the sword.