Containment Priest is excellent here, exiling any nontoken creature that enters without being cast, which shuts down Flickerwisp, Phelia, and Ephemerate's blink effects on creatures and neutralizes Emperor of Bones's reanimation of exiled creatures. Rest in Peace exiles every graveyard and keeps cards from reaching it at all, which blanks Overlord of the Balemurk's mill-and-return trigger and leaves Emperor of Bones with nothing to exile and reanimate. Stubborn Denial and Spell Pierce only counter noncreature spells, so they miss most of their key threats, such as Solitude, Orcish Bowmasters, Phelia, Flickerwisp, and Overlord of the Balemurk, which are all creature spells or enter as creatures. Keep your low curve and Leyline Binding to answer their key threats like Overlord of the Balemurk and stop it from attacking and recurring value again.