Ichorid Its easy to underestimate Ichorid, especially since exiling creatures from your graveyard is a huge cost in a color thats actively trying to do the opposite
In any deck that could play it, youd have no reason not to do so

Aboleth Spawn Abstruse Archaic Adric, Mathematical Genius Ancient Greenwarden Annie Joins Up Annie Joins Up Brokers Confluence Clara Oswald Cloud, Midgar Mercenary Consign to Memory Defabricate Delney, Streetwise Lookout Deny the Witch Detect Intrusion Disallow Drivnod, Carnage Dominus Echo, Perceptive Prodigy Echoes of Eternity Elesh Norn, Mother of Machines Emerald Dragon Emerald Dragon Ertai Resurrected Felix Five-Boots Firebender Ascension Gandalf the White Gogo, Master of Mimicry Green Slime Harmonic Prodigy Isshin, Two Heavens as One Isshin, Two Heavens as One Katara, the Fearless Kirol, Attentive First-Year Krang, the All-Powerful Lithoform Engine Louisoix's Sacrifice Mirror Room // Fractured Realm Mirror Room // Fractured Realm Mister Fantastic Naban, Dean of Iteration Nimble Obstructionist Overcharged Amalgam Panharmonicon Panoptic Projektor Peter Parker's Camera Phenomena Recorder Repudiate // Replicate Repudiate // Replicate Return the Favor Roaming Throne Roaming Throne Sanctum of All Scientist Supreme of A.I.M

So, with that in mind, we doubt it needs too much introduction