Currently, this whole "standard back" argument goes out the window thanks to the printing of Double-Faced cards

The Dungeons Baldur's Gate Wilderness Dungeon of the Mad Mage Lost Mine of Phandelver Tomb of Annihilation Undercity Venture Cards Acererak the Archlich Bar the Gate Clattering Skeletons Delver's Torch Displacer Beast Dungeon Descent Dungeon Map Eccentric Apprentice Ellywick Tumblestrum Fates' Reversal Fifty Feet of Rope Find the Path Fly Immovable Rod Intrepid Outlander Keen-Eared Sentry Kick in the Door Midnight Pathlighter Nadaar, Selfless Paladin Planar Ally Precipitous Drop Radiant Solar Ranger's Hawk Secret Door Sefris of the Hidden Ways Shortcut Seeker Thorough Investigation Triumphant Adventurer Varis, Silverymoon Ranger Veteran Dungeoneer Wandering Troubadour You Find a Cursed Idol Yuan-Ti Fang-Blade Yuan-Ti Malison Zalto, Fire Giant Duke Zombie Ogre Payoff Cards Acererak the Archlich Barrowin of Clan Undurr Cloister Gargoyle Eccentric Apprentice Ellywick Tumblestrum Gloom Stalker Nadaar, Selfless Paladin Precipitous Drop We should also probably mention Dungeon Delver and Hama Pashar, Ruin Seeker

The second was the Initiate cycle
Ignoble Hierarch Exalted often pairs well with a good utility card, and Ignoble Hierarch is no exception
On three occasions in the history of this game, we've had a Standard environment where madness was legal as was this powerhouse
While complete sets are always going to fetch higher prices on average, cards being sold solo are still demanding exuberant prices