msem-instigator

Golden age (If you cast an instant or sorcery spell, activated a nonmana ability, and attacked this turn, enter a renaissance for this game.)
{3}{W}: You gain 1 life.
Sponsor of the Folded Fan gets +2/+0 as long as you're in a renaissance.

Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)
Whenever Stalwart Cathar and at least two other creatures attack, Stalwart Cathar gets +2/+0 until end of turn. Untap it.

Each creature with a law counter on it can't attack or block.
{2}{W}, {T}: Remove all law counters from all permanents, then put a law counter on target creature.

Flying, lifelink

Encourage ({T}: Another target creature you control gets +1/+1 until end of turn. Encourage only as a sorcery.)
Whenever Topan Curemaster encourages a creature, you gain 1 life.

As long as you control three or more artifacts, Treasury Master gets +2/+0 and has slipstream. (This creature can't be blocked as long as only creatures with slipstream are attacking.)

Angel spells you cast cost {1} less to cast.

Warped Recluse can't be blocked by creatures with greater power.
Whenever Warped Recluse attacks and isn't blocked, exile target creature defending player controls. At the beginning of that card's owner's next upkeep, return it to the battlefield under their control.

Flying, lifelink
Creatures entering or leaving the battlefield don't cause abilities to trigger unless that creature is in a pack. (Two or more creatures a player controls with equal power are in a pack.)

When Whiterun Ordainer enters, you gain 4 life.

{T}: Tap target creature. Activate only if Wizened Veteran is embattled. (A creature is embattled if it has a counter on it or a permanent you control attached to it.)

At the beginning of your end step, if you cast no spells this turn, you may return Wrathful Meditant to its owner's hand.

Flash
Rhapsody {5}{U}{U} (Pay {5}{U}{U} to cast this as a 4/4, or once it is in play to make it become a 4/4.)
Animus Channeler's rhapsody cost can be paid any time you could cast an instant.

Flash
Flying
Once during each of your opponent's turns, when you cast a spell, you may pay {1}{U/R}. If you do, copy it. You may choose new targets for the copy. (If it's a permanent spell, the copy becomes a token.)

Flying
Civilized — Whenever Aven Supervisor deals combat damage to a player, if you control an artifact, a creature, and an enchantment, you may draw a card. If you do, discard a card.

Vanguard — Whenever a creature you control attacks alone, it gets +1/+3 until end of turn.

Whenever you cast an enchantment, instant, or sorcery spell, create a 1/1 blue Jellyfish enchantment creature token with slipstream. (It can't be blocked as long as only creatures with slipstream are attacking.)

When Bubblespout Sentry enters, look at the top card of your library. You may put it into your graveyard.

Whenever Canyon Mystic deals combat damage to a player, draw a card.

You may cast spells with mana value 5 or greater as though they had flash.
As long as you control a permanent with mana value 5 or greater, Cenotaph Conjurant gets +2/+0 and can't be blocked.

Whenever another creature named Chef's Apprentice you control enters, target player mills three cards.

Whenever Coral Hunter attacks, another target creature can't be blocked this turn.

Invocation — When you spend four or more mana to cast a spell or activate an ability during your turn, transform Corrupted Sorcerer.

Flash
When Culi-Sae Mesmer enters, return all permanents attached to target permanent or player to their owners' hands.