That might not be terminal in and of itself - again, if we had Block Constructed still, this might be an All-Star - but for Standard (and greater) play it's competing with Farewell at six and Sunfall on multiple dimensions
"These eyes have shown me the flaws of flesh." 3/3
For example, Rowan, Scion of War can make your spells incredibly cheap, and Greven is likely going to be able to one-shot an opponent once the dust settles from Hellfire
The newest set, Wilds of Eldraine, doesn't disappoint in this regard
That's not to say that the deck isn't powerful when it works, but cards like Loki's Double and Lady Loki's Manifestation focus on copying creatures or creature types, while Madame Hydra focuses on creating Villain tokens, and Superior Foes of Spider-Man deals with exiling cards from the top of your library
1 Shivan Dragon