Lets start with Klauth, Unrivaled Ancient
It is after the sharp fall off in quality that the fringe playable equipment in cube become more interesting and up for discussion
First, Gurgling Anointer reanimates a creature with mana value equal to its power, which means if we play it and it immediately dies, it can reanimate a one-drop, which makes having something it can reanimate essential
[[Behind the Scenes]] is already in the deck though

Abigale, Eloquent First-Year Abigale, Poet Laureate Agent of Masks Alms Beast Amalia Benavides Aguirre Angel of Despair Ardbert, Warrior of Darkness Aron, Benalia's Ruin Arvad the Cursed Aryel, Knight of Windgrace Ashen Rider Assault Intercessor Astarion, the Decadent Athreos, God of Passage Athreos, Shroud-Veiled Ayli, Eternal Pilgrim Baron Bertram Graywater Barrowin of Clan Undurr Bartolom del Presidio Basilica Bell-Haunt Black Widow, Double Agent Blind Hunter Blood Baron of Vizkopa Blood-Cursed Knight Bloodied Ghost Breathless Knight Breena, the Demagogue Brimaz, Blight of Oreskos Carmen, Cruel Skymarcher Cartel Aristocrat Chief of the Edge Chief of the Scale Clavileo, First of the Blessed Cleric of Life's Bond Cliffhaven Vampire Cloak and Dagger, Entwined Colonel Autumn Commissar Severina Raine Company Commander Conciliator's Duelist Corpse Knight Cruel Celebrant Dark Leo & Shredder Daxos the Returned Deathbringer Liege Deathpact Angel Defacing Duskmage Denethor, Ruling Steward Divinity of Pride Drana and Linvala Drana's Emissary Edgar, Charmed Groom Edgewalker Elas il-Kor, Sadistic Pilgrim Elder Arthur Maxson Elenda, Saint of Dusk Elenda, the Dusk Rose Embalmed Ascendant Emptiness Eriette of the Charmed Apple Estinien Varlineau Evershrike Extus, Oriq Overlord Felisa, Fang of Silverquill Fiendish Panda Firja, Judge of Valor Fleshtaker Foot Elite Foot Ninjas Frodo, Adventurous Hobbit General Kudro of Drannith General's Enforcer

I dont consider it a deep cut per se, but I do think its an underrated masterpiece thats why theres so much of it in the game