msem-instigator

Tap up to three target creatures.
Compose (Then if you cast this from your hand, exile it and create a Saga token with “r3—You may cast a copy of this card from exile without paying its mana cost.”)

Whenever Practical Battlemage attacks, catalyze. (The next spell you cast this turn costs {1} less to cast.)

Target creature gets +1/+1 until end of turn. When that creature dies this turn, create a 2/2 colorless Spirit creature token.
Inscribe {3}{G} ({3}{G}: Exile this card from your hand inscribed on a creature you control. Whenever that creature attacks, its controller may cast a copy of the inscribed card without paying its mana cost. Inscribe only as a sorcery.)

Vanishing 3
Whenever a time counter is removed from Prayers of Release, you may put a -1/-1 counter on target creature.

When Pre-Crime Handler enters, conjure a card named Data-Point into your hand. You gain 2 life. (It's a sorcery that costs {2} with “Draw a card.”)

Preacher of the Yenzu gets +2/+0 and has flying as long as you control a legendary creature.

When Precursor Custodians enters, exile up to one target creature. As long as that card remains exiled, its owner may cast it. A spell cast this way costs {2} more to cast.

{1}, {T}: Add one mana of any color.
Crew 1 (Tap any number of creatures you control with total power 1 or greater: This Vehicle becomes an artifact creature until end of turn.)

Equipped creature gets +1/+1 and has menace.
Equip {R}

Target creature you control deals damage equal to its power to another target creature. You gain 3 life.

Predatory Abomination has deathtouch and lifelink as long as you control another Horror.

Choose a creature. When it dies this turn, distribute two +1/+1 counters among any number of creatures you control.

Flash
When Predatory Psion enters, switch target creature's power and toughness until end of turn.

Scry 3.
Catalyze. (The next spell you cast this turn costs {1} less to cast.)

You draw two cards and you lose 2 life.
Amass Soldiers 2. (Put two +1/+1 counters on an Army you control. It's also a Soldier. If you don't control one, create an 0/0 black Soldier Army creature token first.)

Creatures you control get +0/+2 until end of turn. Untap those creatures.

Put a +1/+1 counter on target creature.
Draw a card.

You gain 3 life.
Amass Soldiers 1. (Put a +1/+1 counter on an Army you control. It's also a Soldier. If you don't control one, create an 0/0 black Soldier Army creature token first.)

Target creature you control gains double strike until end of turn. That creature also gains trample until end of turn if you control a creature with power 4 or greater.

Enchant creature
Enchanted creature gets +0/+1 and has hexproof.
Mirage {U} (You may cast this spell as though it had flash for its mirage cost. If you do, sacrifice it at the beginning of the next cleanup step.)

Gain control of target non-Pirate, non-Rogue creature until end of turn. Untap that creature. It gains haste until end of turn. Pirates and Rogues you control get +1/+0 until end of turn.

Target creature you control fights target creature you don't control. (Each deals damage equal to its power to the other.)

Draw two cards, then discard two cards. Then if you cast Price of Wisdom from your graveyard, create a 3/3 blue Sphinx creature token with flying.
Flashback {4}{U}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Flying
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)

Haste
{4}{R}: Monstrosity 2. (If this creature isn't monstrous, put two +1/+1 counters on it and it becomes monstrous.)