msem-instigator

Puzzlebox (Begin the game with this and another card you own from outside the game in the command zone, locked. That card is face down until you unlock this.)
{0}: If a player has fifteen or fewer cards in their library, unlock Dreamcast Relic. If the revealed card is blue, put it into your hand. Otherwise, put it on top of your library.

Choose one—
• Counter target spell.
• Exile two target permanents you control, then return them to the battlefield under your control.

When Demonqueller Mage enters, gain control of target creature with power 2 or less until Demonqueller Mage leaves the battlefield.

Counter target spell with mana value 3 or less. If a spell is countered this way, return it to its owner's hand instead of putting it anywhere else.

{1}, Exile Coiling Mystic from your graveyard: Investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

Flying
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
At the beginning of your end step, you may untap another target permanent.

Target creature gets +2/+2 and gains lifelink until end of turn.

If Wandering Domovoi would be dealt noncombat damage, prevent that damage and put three +1/+1 counters on Wandering Domovoi instead.

Whenever Vanguard of the Barricade attacks, tap up to one target creature defending player controls and untap up to one other target creature you control.

Destroy each creature with power 3 or greater.

Flying
When Skymount Reinforcements enters, put a +1/+1 counter on another target creature.

Flying
Tap two untapped creatures you control: Skymount Commander gains double strike until end of turn.

Whenever Sentry of Kollis Gate is dealt damage, put a +1/+1 counter on each other creature you control.

As long as a creature you control has flying, creatures you control have flying. The same is true for first strike, double strike, deathtouch, haste, hexproof, indestructible, lifelink, menace, reach, trample, and vigilance.

When Realmwalker Domovoi enters, exile another target permanent you control. Return it to the battlefield under your control at the beginning of the next end step.

Whenever Pelaski Valiant becomes tapped, target creature gets +1/+1 until end of turn.

Double strike

All damage that would be dealt to target creature you control this turn is dealt to another target creature you control instead. Both those creatures get +1/+1 until end of turn.
Flashback {1}{W} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Return a permanent you control to its owner's hand.
Investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

When Masha's Lightbound becomes tapped for the first time each turn, untap Masha's Lightbound and each other creature you control.
{W}, {T}: Exile target card from a graveyard.

Players can't cast spells with mana value greater than the number of dissent counters on Kazimir's Ban.
{2}: Put a dissent counter on Kazimir's Ban. Any player may activate this ability.

{1}{W}, {T}: Other creatures you control get +1/+1 until end of turn.

Vigilance
Creature spells you cast cost {2} less to cast.
Other creatures you control can't attack or block.

Vigilance
Players can't untap more than two lands during their untap steps.

When Establish Guard enters or leaves the battlefield, create a 1/1 white Human Soldier creature token and you gain 1 life.