msem-instigator

Target player discards two cards. If a creature you control died this turn, that player loses 2 life.

Changeling (This card is every creature type.)
This creature enters with four -1/-1 counters on it.
Whenever another creature you control enters, if that creature has greater power or toughness than this creature, remove a -1/-1 counter from this creature.

{T}: Target creature gains haste until end of turn.
{1}{R}, {T}, Sacrifice a Human: Create a token that's a copy of the sacrificed creature, except it's a 3/2 colorless Horror. It gains haste until end of turn. Activate only as a sorcery.

Whenever Blackfeather Cleric enters or attacks, exile target card from a graveyard. Put a +1/+1 counter on Blackfeather Cleric if it was a permanent card. Otherwise, you gain 1 life.
Surpass {5}{B} ({5}{B}: Transform this creature. This costs {1} less to activate for each counter on it. Activate only as a sorcery.)

Defender
Whenever another creature deals damage to Temperate Gazebo, you gain 3 life.

When Polgek Restorationist enters, you may return target artifact, enchantment, or planeswalker card from your graveyard to your hand.

Whenever an opponent casts a spell, that player gets a poison counter unless they pay {1}.
As long as an opponent has five or more poison counters, Corrupted Soothsayer gets +2/+1 and has flying.

Haste
Arise {2}{R} ({2}{R}, Exile this from your graveyard as a sorcery: Create a black token copy of it that's also a Zombie and can't block.)

Flash
When Frontier Paragon enters, untap all creatures you control.

Flying, haste
{2}{R}{R}, Exile a multicolored card from your graveyard: Return Rainbow Phoenix from your graveyard to the battlefield tapped. If it's your declare attackers step, it enters attacking.

Codex — Eleventh Hour Breakthrough; Mentorb; Ostracizer Orb; Possibility Engine; Sealed Riftway; Self Replication. (As this enters, conjure its contents into a shuffled face-up additional library.)
{T}, Sacrifice an artifact: Draw a card from the codex's library.

When Disciple of the Buried Glade leaves the battlefield, create a 3/3 green Elemental creature token.

Paranoia—Reappropriate white. (You may cast this spell by exiling two white cards from your hand and/or graveyard when a permanent you control leaves the battlefield.)
When Ivenge's Evangel enters, create a 1/1 white Cleric creature token and you gain 1 life.

Reverberate {3}{U} (When you cast this spell, copy it if you paid its reverberate cost.)
If Violent Spasm is reverberated, creatures you control gain flying until end of turn. Violent Spasm deals 1 damage to each creature without flying.

Choose one —
• Return all tapped creatures to their owners' hands.
• Return all untapped creatures to their owners' hands.

When this creature enters, target creature you control gets +1/+1 and gains vigilance until end of turn. You may remove a counter from that creature.

When Lambholt Tracker dies, create a Weapon token. (It's an Equipment artifact with “Equipped creature gets +1/+1” and equip {2}.)
Foreshadow {2}{G} (You may cast this spell for its foreshadow cost. If you do, also trigger its “dies” abilities when it enters.)

Target player discards two cards and loses 2 life. Scry 2. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom of your library and the rest on top in any order.)

You may return a land you control to its owner's hand rather than pay this spell's mana cost.
Northern Express Line enters tapped.
{T}: Add {U}.

Transcend (Activate as a sorcery to gain the next type and a +1/+1 counter.)
Jutou enters with X +1/+1 counters on her.
{3}{G}: Demigod — You gain life equal to the greatest power among creatures you control.
{6}{G}: God — Search your library for a creature card with the same power as a creature you control, put it onto the battlefield, then shuffle.

When Earthenlore Disciple enters, you may destroy target artifact, enchantment, or land.

{T}: Untap another target enchanted creature you control. You may attach target Aura attached to that creature to another creature you control. Activate only as a sorcery.

Put a +1/+1 counter on target creature and a +1/+1 counter on up to one target Citizen or Peasant.

{T}: Add {C}{C}. Spend this mana only to cast spells with mana value 5 or greater.

Trample
Whenever a lore counter is put on a Saga you control, Chimperial Guard gets +2/+2 until end of turn.