The casual fan will often say that Diamond solo and Mercyful Fate are interchangeable. I understand that entirely. There's a nuanced difference (largely named "Andy La Rocque") and, admittedly, it's a little difficult to sometimes move beneath the undeniable presence of King Diamond's vocals to peel back the layers and enjoy both bands. In the end, if you like one there's a damn good chance you'll like the other and, really, any differences don't matter. That said, there's a grind and a heft to the guitars in Mercyful Fate absent from the heavily-melodic work of King Diamond solo. Add in the complex, oft-interwoven lyrical themes and interconnected stories that frequently dominate King Diamond's records and Mercyful Fate brings the listener a more immediate, in-your-face "typical" heavy metal experience (if you can even apply that label to a Diamond-fronted band).