Other cards like Quina, Qu Gourmet and Knuckles the Echidna are from Universes Beyond properties and unlikely to have any other cards with the same creature type
Here are some of my favorite high cmc cards that you can use for way less mana: Casting Our Spells We'll need to produce lots of mana (and ways to cheat on mana!) if we want to cast our high cmc spells

These are some of the best ones I could find: Sin Prodder, Twilight Prophet, Combustible Gearhulk, Sorin, Grim Nemesis, Reviving Vapors, Rush of Knowledge, Ugin's Insight, Interpret the Signs, Nissa's Revelation, Greater Good, Demonlord Belzenlok, Emrakul's Influence Card Draw: Yidris, Maelstrom Wilder, Maelstrom Nexus, Sunbird's Invocation Cascades: Scattering Stroke, Psychic Battle Denial: Timesifter Extra Turns: Favor of the Mighty Protection: Recross the Paths, Selvala, Heart of the Wilds Ramp: Mercurial Chemister, Wolf of Devil's Breach, Riddle of Lightning, Blast of Genius, Disaster Radius, Heretic's Punishment, Kozilek's Return, Nahiri's Wrath, Displacement Wave, Gaze of Granite, Pernicious Deed Removal: Vengeful Rebirth Recursion: Fierce Empath, Treasure Mage, Conduit of Ruin, Grozoth, Sanctum of Ugin Tutors: Spellbound Dragon, Metallurgic Summonings, Kalemne, Disciple of Iroas, Vial Smasher the Fierce, Baneful Omen, Infernal Genesis Beatdown: I'm happy to see that Red is bringing the most value in terms of high cmc support cards

The Prize Race is the most important concept in competitive Pokmon
Is Mega Evolution a good investment
That is a Daze style win right there getting value from something you might not draw, perhaps not even have