For this list cards are considered if they appeared as common in any basic set or expansion set. Cards labeled C1 are less common than normal commons.

Top 20 Greatest Common Cards
  
BEST LAND 
     Maze of Ith (C1) Best Common Land for Utility
      
BEST ARTIFACT 
     Phyrexian War Beast (C1) Best Common Artifact Creature
      
BEST ENCHANTMENT 
     Rancor Best Common Enchant Permanent
      
BEST CREATURES 
     Mogg Fanatic Best Common Burn Creature
     Llanowar/Fyndhorn Elves Best Common Mana Creature
     Order fo Leitbur/Ebon Hand Best Common Combat Creature
     River Boa Best Common Regenerating Creature
     Ophidian Best Common Utility Creature
     Blastoderm Best Common Beatdown Creature
      
BEST UTILITY SPELLS 
     Dark Ritual Best Common Mana Acceleration Spell
      
BEST COUNTER SPELLS 
     Counterspell Best Common Counter Spell
     Arcane Denial (C1) Best Common Cantrip Spell
      
BEST DISCARD SPELLS 
     Hymn to Tourach Best Common Random Discard Spell
     Duress Best Common Targeted Discard Spell
      
BEST BURN SPELLS 
     Lightning Bolt Best Common Burn Spell
     Incinerate Best Common Extended Burn Spell
     Fireblast Best Common Pitch Spell
      
BEST REMOVAL SPELLS 
     Disenchant Best Common Artfct/Encht Removal Spell
     Terminate Best Common Creature Removal Spell
     Sink Hole Best Common Land Destruction Spell
      

Honorable Mention
  
BEST ANTE CARD 
     Diabolic Edict Best Common Non-targeting Removal Spell
     Capsize Best Common Buyback Spell
     Drain Life Best Common Drain Spell
     Empyrial Armor Best Common P/T Enhancement
     Pyroblast/REB/Hydroblast/BEB Best Common Sideboard Spell

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