While accelerating from 1 to 3 doesnt do much, hitting max speed unlocks additional abilities on certain cards
Your notable reprints are Chaos Warp, Niv-Mizzet, Parun, both Will Kenrith and Rowan Kenrith, Solemn Simulacrum, Blasphemous Act, and Curse of Opulence
Reckless: The card cannot quest and they must challenge if theyre able to
Since it's mana free, you can use it when you've tapped out, or cast a mass removal spell like Damnation or Life's Finale to save it proactively not reactively to something else and have the only creature left on the battlefield
Mount Doom Rating: 7/10 Given that this always loses you life if you tap it for mana, much like Horizon Canopy, you cant necessarily rely on it to be a dual land