It has one of the strongest colorless ETB effects in the game, giving you protection the turn you cast it, so you get a nice advantage even if you cast this card in the late game
And while its new, its also familiar, as it reminds us of the old days when red damage hurt you as well, like Char or Orcish Artillery
Soul Summons is a 2-mana 2/2 with potentially huge upside sounds pretty good, while Write Into Being is pretty crazy since you can potentially pick which one you want to cast
Any card that looks at cards in graveyards looks at any or all your graveyards
However, it is strong enough that it was worth playing
Cool bonus one: You can bounce your own madness creature and then discard it automatically (assuming you have a Zombie), madnessing it right back onto the battlefield (but dodging whatever removal spell was pointed at it)