It's worth noting that you do need a payoff for gaining life
Cards with multiple card types are at a premium, so the deck is full of stuff like: Solemn SimulacrumSolemn Simulacrum Dryad ArborDryad Arbor Demonic CovenantDemonic Covenant Theres plenty of self-mill to fill your graveyard: Deadbridge ChantDeadbridge Chant Nyx WeaverNyx Weaver Crawling SensationCrawling Sensation You also have a couple ways to get those cards back, like ReanimateReanimate and Whip of ErebosWhip of Erebos
If your opponent is casting a bunch of four-mana cards, making them pick up their board and making an 8/8 is pretty huge, especially if theyre still in one-spell-per-turn territory
Deadly Cover-Up is still no Sunfall, but it does a lot
Razorlash Transmogrant Like many of the artifacts in the set, Razorlash Transmogrant is a robotic version of an already-existing Magic card, in this case any number of black creatures like Despoiler of Souls or Aunties Snitch (or Gravecrawler, or Bloodghast, or Falkenrath Forebear, or Skyclave Shade, or Bloodsoaked Champion or) that cant block, have a greater power than toughness, and can come back to life, a subset of creatures that is much larger than one would expect given the conditions
