Hellkite Courser and the $9 Sarkhan, Soul Aflame both recently spiked because of Tarkir: Dragonstorm , so those should settle back down
The myriad of objects and foliage surrounding Galarian Slowking are so nuanced and detailed, that you'd struggle to count them all
Many Rayquazas are worth plenty of money with shiny printings, Mega Evolution power-ups, and full art cards going for hundreds of dollars on the market
Craterhoof Behemoth is the gold standard, but pretty much any of these effects are good

Aang and Katara Aang and La, Ocean's Fury Aang, A Lot to Learn Aang, Air Nomad Aang, Airbending Master Aang, Destined Savior Aang, Master of Elements Aang, Swift Savior Aang, at the Crossroads Aang, the Last Airbender Affa Protector Agadeem Occultist Akiri, Line-Slinger Akoum Battlesinger Akoum Flameseeker Angel of Renewal Angelic Captain Appa, Aang's Companion Appa, Loyal Sky Bison Appa, Steadfast Guardian Appa, the Vigilant Avatar Aang Avatar Enthusiasts Bala Ged Thief Beastcaller Savant Bloodbond Vampire Boiling Rock Rioter Bojuka Brigand Bruse Tarl, Boorish Herder Bruse Tarl, Boorish Herder Bumi, Eclectic Earthbender Bumi, King of Three Trials Bumi, Unleashed Chasm Guide Chong and Lily, Nomads Cliffhaven Vampire Cliffside Lookout Compassionate Healer Coralhelm Guide Deserter's Disciple Diligent Zookeeper Drana's Chosen Drana's Emissary Drana, Liberator of Malakir Earth King's Lieutenant Earth Kingdom General Earth Kingdom Jailer Earth Kingdom Protectors Earthbending Student Earthen Ally Expedition Envoy Fire Lord Zuko Firemantle Mage First-Time Flyer Flexible Waterbender Foggy Swamp Hunters Foggy Swamp Spirit Keeper Foggy Swamp Vinebender Forecasting Fortune Teller Freedom Fighter Recruit General Tazri Geyser Leaper Glider Kids Goblin Freerunner Gran-Gran Graypelt Hunter Great Divide Guide Grovetender Druids Guru Pathik Hada Freeblade Hagra Diabolist Hagra Sharpshooter

This one card will often take down three of the biggest threats on the battlefield for just three mana