Its a pretty subjective word, but in general, it refers to the common, uncommon, and occasionally rare cards that individually have little value
How about some newer Reserve List cards in that case
What affects the value of Obliterate
5-Color Niv-Mizzet by Michael Rapp 2 Paradise Druid 4 Sylvan Caryatid 1 Dreadbore 2 Abrupt Decay 4 Teferi, Time Raveler 1 Unmoored Ego 1 Deafening Clarion 3 Uro, Titan of Natures Wrath 1 Supreme Verdict 1 Utter End 1 Nahiri, the Harbinger 3 Siege Rhino 1 The Scarab God 1 Tolsimir, Friend to Wolves 4 Bring to Light 3 Niv-Mizzet Reborn 1 Cut // Ribbons 2 Botanical Sanctum 4 Fabled Passage 1 Forest 1 Godless Shrine 1 Island 2 Mana Confluence 1 Mountain 2 Opulent Palace 1 Overgrown Tomb 1 Plains 2 Sandsteppe Citadel 2 Spirebluff Canal 2 Stomping Ground 1 Swamp 2 Temple Garden 1 Watery Grave That makes my choice of flex slots: 1 Dreadbore 1 Unmoored Ego 1 Deafening Clarion 1 Uro, Titan of Natures Wrath 1 Nahiri, the Harbinger 1 Siege Rhino 1 The Scarab God 1 Tolsimir, Friend to Wolves 1 Cut // Ribbons As you can see, I went into the weekend ready for aggressively-slanted creature decks, like Mono-Red and Mono-Black