msem-instigator

Target player mills X cards, where X is the number of cards in your graveyard.
Flashback {3}{U/B}{U/B} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Destroy target nonbasic land.
Abound. (To abound, you may cast a spell that costs less than this from your hand without paying its mana cost.)

You may play an additional land on each of your turns.
Whenever Antali Archdruid attacks, if two or more lands entered the battlefield under your control this turn, Antali Archdruid deals 3 damage to any target and you gain 3 life.

Flying
When Cadre Hawk enters the battlefield, you may search your library and/or graveyard for a card named Cadre Hawk, reveal it, and put it into your hand. If you searched a library this way, shuffle.

Target opponent chooses a card type, then reveals their hand. You choose a card from it that's not of the chosen type. That player discards that card.

Enchant creature
You control enchanted creature.
Enchanted creature gets +1/+1 and has slipstream. (This creature can't be blocked as long as only creatures with slipstream are attacking.)

Flash
If a spell or ability an opponent controls would cause you to discard a creature card, you may put that card onto the battlefield instead.

(As you complete a condition, decode it. After all are decoded, you solve the mystery and transform this.)
When Mystery of the Crashed Craft enters the battlefield, create a 1/1 red Alien creature token.
{MG} — You cast an instant spell.
{MG} — You cast a sorcery spell.

Counter target instant or sorcery spell unless its controller pays {3}.

Flash
TT-23 Aegis can't attack or block unless you have six or more cards in hand.
At the beginning of your end step, if you didn't cast a spell this turn, draw a card.

Constructs you control have haste.
When Urak, Voice of the Horde or another Construct enters the battlefield under your control, creatures you control get +1/+0 until end of turn.
Respawn (When this creature dies, if it attacked this turn, return it to your hand.)