X can't be greater than the number of players in the game.

Reveal cards from the top of your library until you reveal X land cards. Put those land cards onto the battlefield tapped and the rest on the bottom of your library in a random order.

Whenever Ophidian attacks and isn't blocked, you may draw a card. If you do, Ophidian assigns no combat damage this turn.

At the beginning of each upkeep, if you control no Snakes, create a 1/1 black Snake creature token with deathtouch.

Flying

When Opportunistic Dragon enters, choose target Human or artifact an opponent controls. For as long as Opportunistic Dragon remains on the battlefield, gain control of that permanent, it loses all abilities, and it can't attack or block.

Tap an untapped creature you control: Tap target artifact, creature, or land.

Whenever a player casts a spell, that player discards a card.

Counter target spell unless its controller pays for each card in your hand.

Whenever you crank Optical Optimizer, until end of turn, target creature becomes an artifact in addition to its other types and gains ": Draw a card."

More Than Meets the Eye (You may cast this card converted for .)

At the beginning of each end step, bolster 1. (Choose a creature with the least toughness among creatures you control and put a +1/+1 counter on it.)

When Optimus Prime dies, return it to the battlefield converted under its owner's control.

: Untap target attacking creature you control and remove it from combat.

Haste

Tribute 2 (As this creature enters, an opponent of your choice may put two +1/+1 counters on it.)

When Oracle of Bones enters, if tribute wasn't paid, you may cast an instant or sorcery spell from your hand without paying its mana cost.

You may play an additional land on each of your turns.

Play with the top card of your library revealed.

You may play lands from the top of your library.

When Oracle of Tragedy enters or dies, choose one —

• Draw a card, then discard a card.

• Shuffle up to four target cards with mana value 3 or greater from your graveyard into your library.

Enchant creature

Enchanted creature has ": Scry 1, then draw a card." (To scry 1, look at the top card of your library, then you may put that card on the bottom.)

Lifelink

Whenever Orah, Skyclave Hierophant or another Cleric you control dies, return target Cleric card with lesser mana value from your graveyard to the battlefield.

: Oran-Rief Invoker gets +5/+5 and gains trample until end of turn.

Kicker (You may pay an additional as you cast this spell.)

Reach (This creature can block creatures with flying.)

When Oran-Rief Recluse enters, if it was kicked, destroy target creature with flying.

Oran-Rief, the Vastwood enters tapped.

: Add .

: Put a +1/+1 counter on each green creature that entered this turn.

Protection from red

, , Sacrifice Orazca Puzzle-Door: Look at the top two cards of your library. Put one of those cards into your hand and the other into your graveyard.

Ascend (If you control ten or more permanents, you get the city's blessing for the rest of the game.)

: Add .

, Sacrifice Orazca Relic: You gain 3 life and draw a card. Activate only if you have the city's blessing.

Permanents enter tapped.

Reach (This creature can block creatures with flying.)

Whenever you cast a Spirit or Arcane spell, Orbweaver Kumo gains forestwalk until end of turn. (It can't be blocked as long as defending player controls a Forest.)

Whenever another creature you control enters, target creature an opponent controls gets -1/-1 until end of turn.

Council's dilemma — When Orchard Elemental enters, starting with you, each player votes for sprout or harvest. Put two +1/+1 counters on Orchard Elemental for each sprout vote. You gain 3 life for each harvest vote.

When Orchard Strider enters, create two Food tokens. (They're artifacts with ", , Sacrifice this artifact: You gain 3 life.")

Basic landcycling (, Discard this card: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.)

: Orcish Artillery deals 2 damage to any target and 3 damage to you.

Flash

When Orcish Bowmasters enters and whenever an opponent draws a card except the first one they draw in each of their draw steps, Orcish Bowmasters deals 1 damage to any target. Then amass Orcs 1.

: Orcish Cannoneers deals 2 damage to any target and 3 damage to you.

Orcish Conscripts can't attack unless at least two other creatures attack.

Orcish Conscripts can't block unless at least two other creatures block.

, : Target creature can't be regenerated this turn.

, : Regenerate target black or green creature.

, : Regenerate target black or green creature.

, : Look at the top eight cards of your library. Exile four of them at random, then put the rest on top of your library in any order.

, Sacrifice an artifact: Orcish Mechanics deals 2 damage to any target.

Enchant land

Orcish Mine enters with three ore counters on it.

At the beginning of your upkeep and whenever enchanted land becomes tapped, remove an ore counter from Orcish Mine.

When the last ore counter is removed from Orcish Mine, destroy enchanted land and Orcish Mine deals 2 damage to that land's controller.

When Orcish Paratroopers enters, flip it from a height of at least one foot. Sacrifice Orcish Paratroopers unless it turns over completely at least once during the flip and lands face up.

Trample

Other Orcs and Goblins you control have trample.

Whenever Orcish Siegemaster attacks, it gets +X/+0 until end of turn, where X is the greatest power among creatures you control.

Whenever Orcish Squatters attacks and isn't blocked, you may gain control of target land defending player controls for as long as you control Orcish Squatters. If you do, Orcish Squatters assigns no combat damage this turn.

, Sacrifice an artifact: Orcish Vandal deals 2 damage to any target.

Flying, trample

When Orcus, Prince of Undeath enters, choose one —

• Each other creature gets -X/-X until end of turn. You lose X life.

• Return up to X target creature cards with total mana value X or less from your graveyard to the battlefield. They gain haste until end of turn.

Enchant creature

Whenever enchanted creature attacks, put a +1/+1 counter on it. Then if it has three or more +1/+1 counters on it, sacrifice Ordeal of Heliod.

When you sacrifice Ordeal of Heliod, you gain 10 life.

Enchant creature

Whenever enchanted creature attacks, put a +1/+1 counter on it. Then if it has three or more +1/+1 counters on it, sacrifice Ordeal of Purphoros.

When you sacrifice Ordeal of Purphoros, it deals 3 damage to any target.

Exile target attacking creature.

Flying

Order of Midnight can't block.

Choose left or right. Starting with you and proceeding in the chosen direction, each player chooses a creature controlled by the next player in that direction. Each player gains control of the creature they chose.

Protection from white

: Order of the Ebon Hand gains first strike until end of turn.

: Order of the Ebon Hand gets +1/+0 until end of turn.

: Transform Order of the Mirror. Activate only as a sorcery. ( can be paid with either or 2 life.)

, Pay 1 life: Counter target black spell.

Protection from black

: Order of the White Shield gains first strike until end of turn.

: Order of the White Shield gets +1/+0 until end of turn.

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)

Whenever Order of Yawgmoth deals damage to a player, that player discards a card.

Orderly Plaza enters tapped.

: Add or .