Name: Open the Armory Cost: 1W Type: Sorcery Rules Text: Search your library for an Aura or Equipment card, reveal it, put it into your hand, then shuffle. Set/Rarity: Shadows over Innistrad uncommon, Secret Lair Drop rare, Commander Legends uncommon, Pioneer Masters uncommon Price: $2.52

Name: Open the Graves Cost: 3BB Type: Enchantment Rules Text: Whenever a nontoken creature you control dies, create a 2/2 black Zombie creature token. Set/Rarity: Core Set 2019 rare, Core Set 2019 Promos rare, Midnight Hunt Commander rare, Starter Commander Decks rare Price: $0.38

Name: Open the Vaults Cost: 4WW Type: Sorcery Rules Text: Return all artifact and enchantment cards from all graveyards to the battlefield under their owners' control. (Auras with nothing to enchant remain in graveyards.) Set/Rarity: Magic 2010 rare, Commander 2015 rare, Commander 2016 rare, Double Masters rare, Fallout rare Price: $0.37

Name: Ophiomancer Cost: 2B Type: Creature -- Human Shaman Pow/Tgh: 2/2 Rules Text: At the beginning of each upkeep, if you control no Snakes, create a 1/1 black Snake creature token with deathtouch. Set/Rarity: Commander 2013 rare, Commander Collection: Black rare, Historic Anthology 6 rare, Jumpstart 2022 rare, Modern Horizons 3 rare, Tarkir: Dragonstorm Commander rare, Secrets of Strixhaven Commander rare Price: $0.97

Name: Opposition Agent Cost: 2B Type: Creature -- Human Rogue Pow/Tgh: 3/2 Rules Text: Flash You control your opponents while they're searching their libraries. While an opponent is searching their library, they exile each card they find. You may play those cards for as long as they remain exiled, and you may spend mana as though it were mana of any color to cast them. Set/Rarity: Magic Online Promos rare, Commander Legends rare, Commander Legends Promos rare, Through the Omenpaths Bonus Sheet mythic, Marvel Universe mythic Price: $20.76

Name: Oppression Cost: 1BB Type: Enchantment Rules Text: Whenever a player casts a spell, that player discards a card. Set/Rarity: Urza's Saga rare, Seventh Edition rare, Secret Lair Drop rare, The List rare, Wilds of Eldraine: Enchanting Tales rare Price: $3.58

Name: Oppressive Rays Cost: W Type: Enchantment -- Aura Rules Text: Enchant creature Enchanted creature can't attack or block unless its controller pays {3}. Activated abilities of enchanted creature cost {3} more to activate. Set/Rarity: Journey into Nyx common, Magic 2015 common Price: $0.08

Name: Optimistic Scavenger Cost: W Type: Creature -- Human Scout Pow/Tgh: 1/1 Rules Text: Eerie -- Whenever an enchantment you control enters and whenever you fully unlock a Room, put a +1/+1 counter on target creature. Set/Rarity: Duskmourn: House of Horror uncommon Price: $0.27

Name: Oracle en-Vec Cost: 1W Type: Creature -- Human Wizard Pow/Tgh: 1/1 Rules Text: {T}: Target opponent chooses any number of creatures they control. During that player's next turn, the chosen creatures attack if able, and other creatures can't attack. At the beginning of that turn's end step, destroy each of the chosen creatures that didn't attack this turn. Activate only during your turn. Set/Rarity: Tempest rare Price: $0.59

Name: Oracle's Attendants Cost: 3W Type: Creature -- Human Soldier Pow/Tgh: 1/5 Rules Text: {T}: All damage that would be dealt to target creature this turn by a source of your choice is dealt to this creature instead. Set/Rarity: Nemesis rare, Eighth Edition rare, Ninth Edition rare Price: $0.19

Name: Oracle's Vault Cost: 4 Type: Artifact Rules Text: {2}, {T}: Exile the top card of your library. Until end of turn, you may play that card. Put a brick counter on this artifact. {T}: Exile the top card of your library. Until end of turn, you may play that card without paying its mana cost. Activate only if there are three or more brick counters on this artifact. Set/Rarity: Magic Online Promos rare, Amonkhet rare, Amonkhet Promos rare, New Capenna Commander rare Price: $0.29

Name: Orah, Skyclave Hierophant Cost: 2WB Type: Legendary Creature -- Kor Cleric Pow/Tgh: 3/3 Rules Text: Lifelink Whenever Orah or another Cleric you control dies, return target Cleric card with lesser mana value from your graveyard to the battlefield. Set/Rarity: Magic Online Promos rare, Zendikar Rising rare, Zendikar Rising Promos rare Price: $0.23

Name: Orator of Ojutai Cost: 1W Type: Creature -- Bird Monk Pow/Tgh: 0/4 Rules Text: As an additional cost to cast this spell, you may reveal a Dragon card from your hand. Defender, flying When this creature enters, if you revealed a Dragon card or controlled a Dragon as you cast this spell, draw a card. Set/Rarity: Magic Online Promos uncommon, Friday Night Magic 2015 rare, Dragons of Tarkir uncommon, Commander 2017 uncommon Price: $0.16

Name: Orazca Relic Cost: 3 Type: Artifact Rules Text: Ascend (If you control ten or more permanents, you get the city's blessing for the rest of the game.) {T}: Add {C}. {T}, Sacrifice this artifact: You gain 3 life and draw a card. Activate only if you have the city's blessing. Set/Rarity: Rivals of Ixalan common, Forgotten Realms Commander common Price: $0.13

Name: Orb of Dreams Cost: 3 Type: Artifact Rules Text: Permanents enter tapped. Set/Rarity: Betrayers of Kamigawa rare Price: $2.90

Name: Orbs of Warding Cost: 5 Type: Artifact Rules Text: You have hexproof. (You can't be the target of spells or abilities your opponents control.) If a creature would deal damage to you, prevent 1 of that damage. Set/Rarity: Magic Origins rare Price: $0.56

Name: Orc Sureshot Cost: 3B Type: Creature -- Orc Archer Pow/Tgh: 4/2 Rules Text: Whenever another creature you control enters, target creature an opponent controls gets -1/-1 until end of turn. Set/Rarity: Fate Reforged uncommon, The List uncommon Price: $0.20

Name: Orcish Bowmasters Cost: 1B Type: Creature -- Orc Archer Pow/Tgh: 1/1 Rules Text: Flash When this creature enters and whenever an opponent draws a card except the first one they draw in each of their draw steps, this creature deals 1 damage to any target. Then amass Orcs 1. Set/Rarity: Tales of Middle-earth Promos rare, The Lord of the Rings: Tales of Middle-earth rare, The Hobbit Eternal mythic Price: $48.50

Name: Orcish Medicine Cost: 1B Type: Instant Rules Text: Target creature gains your choice of lifelink or indestructible until end of turn. Amass Orcs 1. (Put a +1/+1 counter on an Army you control. It's also an Orc. If you don't control an Army, create a 0/0 black Orc Army creature token first.) Set/Rarity: The Lord of the Rings: Tales of Middle-earth common Price: $0.27

Name: Orcrist, Goblin-cleaver Cost: 3 Type: Legendary Artifact -- Equipment Rules Text: Equipped creature gets +2/+2 and has trample. Whenever equipped creature deals combat damage to a player, choose a creature type. Create a Treasure token for each creature you control of that type. Equip {3} Set/Rarity: The Hobbit mythic Price: $11.56