Well, first off, this should be in #gaming, as well as #grammarandpunctuationcontainedmaybednageroustoIQ. But, to answer your question, the hammer has a small amount of splash damage. You often don't have to get point blank in someone's face, or even into lunge range. Somewhere just outside of lunge range is an area where you can still one-hit someone. Try and attack when you're in that range, as opposed to closer. Also, don't face a Grif head on. He can parry your blow with a melee and still OHKO you with the same attack easily, so if he's facing you he can kill you without breaking stride. You have to flank them, or keep them at bay with the splash from the hammer.