Enchant creature or enchantment
Enchanted permanent is an enchantment and loses all other card types. (It still has its abilities, but it's no longer a creature.)

Whenever you roll a 3 or higher, Monoxa gains first strike until end of turn. If the roll was 4 or higher, it gains menace until end of turn. If the roll was 5 or higher, it gains lifelink until end of turn.
: Roll a six-sided die.

As this enchantment enters, choose an artist.
Creatures with art by the chosen artist get +2/+2.

Trample, haste
Lupine Harbingers enters the battlefield with X +1/+1 counters on it, where X is the number of turns you've begun since it was foretold.
Foretell (During your turn, you may pay and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Green enchantment spells and white enchantment spells cost more to cast.

If an opponent who controls at least as many lands as you do would put a land onto the battlefield, that player instead puts that land onto the battlefield then sacrifices a land of their choice.

Starting with you, each player may put a permanent card from their hand onto the battlefield. Repeat this process until no one puts a card onto the battlefield.

You may look at the top card of your library any time.
You may cast common spells from the top of your library.
Guests you control get +1/+1.

The Legend of Arena can be your commander.
I, II — Create a 2/1 red Human Wizard creature token. Spells you cast this turn cost less to cast for each Wizard you control.
III — Search your library for a planeswalker card, put it onto the battlefield, then shuffle your library. It enters with an additional loyalty counter on it for each Wizard you control.

Whenever The Fifteenth Doctor enters or attacks, mill three cards. You may put an artifact card with mana value 2 or 3 from among them into your hand.
The first nonartifact spell you cast each turn has improvise. (Your artifacts can help cast that spell. Each artifact you tap after you're done activating mana abilities pays for .)

As an additional cost to cast this spell, sacrifice a creature.
Gain control of target nonartifact, nonblack creature.

, Sacrifice a green creature: Target land becomes a Forest. (This effect lasts indefinitely.)

Cumulative upkeep—Exile the top card of your library. (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
When a player doesn't pay this enchantment's cumulative upkeep, that player exiles all cards from their library.
Exile the top card of your library: Prevent the next 1 damage that would be dealt to you this turn.

Double strike, trample, haste
Whenever one or more creatures you control deal combat damage to a player, create a Treasure token.
Treasure Hunter — At the beginning of your upkeep, if you control thirty or more artifacts, you win the game.

: This artifact deals 1 damage to any target. Destroy this artifact at the beginning of the next end step. Activate only if you've controlled this artifact continuously since the beginning of your most recent turn.

Flying
When this creature enters, draw a card at the beginning of the next turn's upkeep.

Whenever you cast your second spell each turn, draw a card, then create a 0/3 white Wall creature token with defender.
At the beginning of combat on your turn, creatures you control with defender gain exalted until end of turn. (Whenever a creature you control attacks alone, it gets +1/+1 until end of turn for each instance of exalted among permanents you control.)

Choose two target creatures controlled by the same opponent. That player chooses and sacrifices one of those creatures. Put a -1/-1 counter on the other.

, : Spin this artifact in the middle of the table so that it rotates completely at least once, then destroy the closest permanent the finger points to.

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)

Brazen Boarding deals 4 damage to target creature or planeswalker. If excess damage is dealt this way, conjure a card with mana value equal to that excess damage from Brazen Boarding's spellbook onto the battlefield. If that excess damage is 4 or greater, instead conjure a card named Admiral Beckett Brass onto the battlefield.

This spell costs less to cast if you have no other creature cards in hand or if the only other creature cards in your hand are named Mothrider Cavalry.
Flying
Other creatures you control get +1/+1.

: Add . Spend this mana only to cast artifact spells or activate abilities of artifacts.
Partner—Friends forever (You can have two commanders if both have this ability.)

, Exile the top two cards of your library: This artifact deals 1 damage to each creature with flying and each player.

Flying
, : Target creature gets +2/+2 until end of turn.

Menace
Whenever Miss Highwater deals combat damage to a player who doesn't have a contract counter, they may discard their hand. If they do, they draw seven cards and get a contract counter. For as long as they have a contract counter, when they lose the game, for each artifact and creature they controlled, create a token that's a copy of it.

When this creature dies, each opponent loses 2 life and you gain 2 life.

At the beginning of your upkeep, you may ask target player a yes-or-no question. If you do, that player answers the question truthfully and abides by that answer if able until end of turn.

, Discard a card: Put a +1/+1 counter on target creature or that creature gains banding, first strike, or trample. (This effect lasts indefinitely. Any creatures with banding, and up to one without, can attack in a band. Bands are blocked as a group. If any creatures with banding a player controls are blocking or being blocked by a creature, that player divides that creature's combat damage, not its controller, among any of the creatures it's being blocked by or is blocking.)

Creatures named Scissors Lizard can't attack or block.

As this enchantment enters, you lose life equal to your life total.
You don't lose the game for having 0 or less life.
If you would gain life, draw that many cards instead.
Whenever you're dealt damage, sacrifice that many nontoken permanents. If you can't, you lose the game.
When this enchantment is put into a graveyard from the battlefield, you lose the game.

Enchant creature
Enchanted creature loses flying.
Whenever enchanted creature blocks or becomes blocked by a creature, the other creature gains first strike until end of turn.

Put a manabond counter on all creatures. (They lose all other abilities and become lands with ": Add one mana of this card's color.")

As this creature enters, choose a word with four or more letters.
Spells with the chosen word in their text box can't be cast.

When this creature enters, target opponent loses 2 life and you gain 2 life.

Defender (This creature can't attack.)
: Regenerate this creature.