msem-instigator

Bleed {2}{R} (You may cast this spell for its bleed cost if an opponent has lost life this turn.)
Target player loses 2 life. If this spell's bleed cost was paid, it deals 1 damage to each creature that player controls.

Glitch {2} (Remove one [restriction] for each time you pay the glitch cost.)
Improbable Aim deals damage to target creature or planeswalker equal to the number of [instant and sorcery] cards in your graveyard.

Chamber of Splendor enters tapped.
When Chamber of Splendor enters, you may pay {1}. If you do, create a Treasure token. (It's an artifact with “{T}, Sacrifice this artifact: Add one mana of any color.”)
{T}: Add {C}.

Trample, haste
Thriving Hydra enters with four +1/+1 counters on it.
When Thriving Hydra enters, for each other creature you control, put X +1/+1 counters on that creature, where X is four minus its power.
Whenever Thriving Hydra attacks, double the number of +1/+1 counters on each creature you control.

Equipped creature gets +2/+0 and has “{T}, Unattach Javelin: It deals 2 damage to target creature.”
Equip {2}

Choose up to two target creatures. For each of those creatures, you may tap or untap it.
Scry 1. (To scry 1, look at the top card of your library. You may put that card on the bottom of your library.)

Target player mills five cards.
Draw a card.

Whenever Slyten Connoisseur attacks, crystallize. (Put a +1/+1 counter on a creature you control or create a Treasure.)
Once each turn, when an artifact you control dies, you may pay 1 life. If you do, draw a card.

Promenade Banner enters tapped.
{1}, {T}: Creatures you control get +1/+1 until end of turn.

Distorted (This creature can be blocked by tapped creatures but not untapped creatures.)
Creature tokens you control have lifelink.

When Goblin Sniper dies, you may pay {R}. If you do, it deals 2 damage to target opponent or planeswalker.

Target opponent chooses a number. When they do, choose one —
• That player discards their hand, then draws cards equal to the chosen number.
• Archivist's Torment deals damage to that player equal to the chosen number.

Search your library for a permanent card with mana value 3 or less and put it onto the battlefield, then shuffle.
Motley — Then if there are five or more names among nonland permanents you control, you gain 7 life.

Flying
Whenever Hao'Tai deals combat damage to a player, that player exiles the top five cards of their library and separates them into two piles. Put an ember counter on each card in the pile of your choice. You may play cards from exile with ember counters for as long as they remain exiled.

When Channeler of the Veil enters, create a 1/1 colorless Construct artifact creature token.
Sacrifice another creature: Each opponent loses 1 life.

At the beginning of each player's upkeep, put a darkness counter on target nonland permanent they control. That permanent is black for as long as it has a darkness counter on it. Then if there are five or more nonland permanents on the battlefield and they are all black, you may exile Tahiel, Elder Kalku and gain control of target creature or planeswalker.

Return target nonland permanent to its owner's hand.
Reconstruct {5}{U} (You may cast this from your graveyard for its reconstruct cost reduced by the mana value of a permanent you sacrifice as you cast it this way. Then exile this.)

Whenever you cast a noncreature spell, torment each opponent. (They lose 3 life unless they discard a card or sacrifice a nonland permanent.)
{3}{U/B}{U/B}: Draw a card for each opponent with ten or more cards in their graveyard. You lose that much life.

At the beginning of your upkeep, each opponent mills cards equal to the number of card types among permanents you control.

Creatures you control gain deathtouch until end of turn and must be blocked this turn if able.

{1}, Sacrifice a creature: Ever-Hungry Tanbaly gains indestructible until end of turn. Tap it.

When Backstage Tinkers enters, you may return an artifact card from your graveyard to your hand.

{T}: Add {C}.
{T}, Reappropriate: Add {U} or {R}. (Exile exactly two cards from your hand and/or graveyard.)

At the beginning of combat on your turn, target creature you control has base power and toughness 5/5 until end of turn.

Haste (This creature can attack and {T} as soon as it comes under your control.)
Double strike (This creature deals both first-strike and regular combat damage.)