"Dead as a doornail" is a phrase used to describe something that is unquestionably lifeless. But, if you're looking for a variation on this expression, "as dead as a dodo," "as dead as a daisy," or even "as dead as a stone" are all great options. Another possibility is "as dead as a battery," which draws a comparison between the lifeless object and a depleted battery. If you're after a more imaginative alternative, "as dead as a coffin handle" or "as dead as a hammer" are particularly evocative choices. Regardless of which phrase you choose, you can feel confident knowing that you've opted for an accurate and expressive way to convey the idea of lifelessness.