Haste
Whenever you cast a spell, if it's the second creature spell you cast this turn, you may return this card from your graveyard to the battlefield.

, Sacrifice this artifact: Return target creature to its owner's hand.
, Sacrifice this artifact: Draw a card.

For Mirrodin! (When this Equipment enters, create a 2/2 red Rebel creature token, then attach this to it.)
Equipped creature gets +2/+2.
Whenever equipped creature attacks, if it's the first combat phase of the turn, untap each attacking creature. After this phase, there is an additional combat phase.
Equip

Flash
Whenever a creature you control deals combat damage to a player, draw a card.
When Enduring Curiosity dies, if it was a creature, return it to the battlefield under its owner's control. It's an enchantment. (It's not a creature.)

This spell can't be countered.
, : You may put a creature card from your hand onto the battlefield. If it's a Wolf or Werewolf, untap this creature. Activate only as a sorcery.
Daybound (If a player casts no spells during their own turn, it becomes night next turn.)

When this creature enters, target opponent loses life equal to the number of Elves you control.

Haste (This creature can attack and as soon as it comes under your control.)
Other Goblin creatures you control get +1/+1 and have haste.

Whenever you tap a Forest for mana, add an additional .
+1: Put three +1/+1 counters on up to one target noncreature land you control. Untap it. It becomes a 0/0 Elemental creature with vigilance and haste that's still a land.
−8: You get an emblem with "Lands you control have indestructible." Search your library for any number of Forest cards, put them onto the battlefield tapped, then shuffle.

When you unlock this door, create three 1/1 red Devil creature tokens with "When this token dies, it deals 1 damage to any target."
(You may cast either half. That door unlocks on the battlefield. As a sorcery, you may pay the mana cost of a locked door to unlock it.)

Flash
If an opponent would draw a card except the first one they draw in each of their draw steps, instead that player skips that draw and you draw a card.

Choose two —
• Create a 2/2 colorless Construct artifact creature token.
• Put a +1/+1 counter on a creature you control. It gains double strike until end of turn.
• Search your library for a basic Plains card, reveal it, put it into your hand, then shuffle.
• You gain 2 life and scry 2.

As this creature enters, choose a creature type.
This creature is the chosen type in addition to its other types.
Other creatures you control of the chosen type get +1/+1.

This land enters tapped unless you control an Island or a Mountain.
: Add or .

Target player activates a mana ability of each land they control. Then that player loses all unspent mana and you add the mana lost this way.

: Switch each creature's power and toughness until end of turn.

Whenever you play a land or cast a spell, draw a card.
At the beginning of your end step, your life total becomes half your starting life total, rounded up.

+1: Target player draws two cards, then discards two cards.
−2: Gain control of target artifact.
−6: You get an emblem with "Whenever you cast a spell that targets one or more permanents, gain control of those permanents."

Menace, lifelink, indestructible
Ketramose can't attack or block unless there are seven or more cards in exile.
Whenever one or more cards are put into exile from graveyards and/or the battlefield during your turn, you draw a card and lose 1 life.

: The next time a red source of your choice would deal damage to you this turn, prevent that damage.

When this creature dies, search your library for any number of creature cards with total mana value 6 or less, put them onto the battlefield, then shuffle.