msem-instigator

Whenever Dancing Lion attacks, if it was crewed by two or more creatures in the same pack this turn, create a tapped and attacking token that's a copy of one of them. Sacrifice the token at the beginning of the next end step. (Two or more creatures you control with equal power are in a pack.)
Crew 2

At the beginning of combat on your turn, you may pay 3 life. If you do, target creature seeks secrets or valor. (Give it that Oath Aura. Fulfill secrets by attacking with it and two or more other creatures to draw a card. Fulfill valor by dealing combat damage to a player to create a 2/1 white Soldier token.)
Whenever you fulfill an Oath, each opponent sacrifices a nonland permanent.

Blazing Exultation deals 3 damage to any target.
{2}{R}: Shuffle Blazing Exultation and up to one other instant or sorcery card from your graveyard into your library.

Defender
When Immured Fiend enters, target opponent discards two cards.

{1}{R}{W}: Create a 2/1 red and white Fox creature token. It gains haste. Sacrifice it at the beginning of the next end step.
Whenever Fox of a Brisk Autumn attacks, attacking Foxes you control get +1/+1 until end of turn.

Flying, prowess
Whenever an artifact you control enters, you may draw a card. If you do, discard a card.

Whenever Kessig Jeweler attacks, you may discard a card. If you do, draw a card.
{1}{R}: Transform Kessig Jeweler. Activate only if it's attacking.

Primal {2}{U}{U} (During your turn, you may cast this spell for {2}{U}{U} instead of playing a land.)
Whenever Tangleveil Mystic deals combat damage to a player, draw cards equal to the number of cards in your hand.

Golden age (If you cast an instant or sorcery spell, activated a nonmana ability, and attacked this turn, enter a renaissance for this game.)
{T}: Add {C}. If you're in a renaissance, add one mana of any color instead.
{3}, {T}: Scry 1.

Whenever a creature attacks you or a planeswalker you control, that creature's controller mills a card.

Whenever you cast a green or blue spell, create a 1/1 green and blue Elemental creature token.
Each Elemental you control enters with an additional +1/+1 counter on it.

Kicker {1}{G} (You may pay an additional {1}{G} as you cast this spell.)
When Mold Shambler enters, if it was kicked, destroy target noncreature permanent.

Deathtouch

Look at the top seven cards of your library. Put two of them into your hand and the rest into your graveyard.

Trample
When Stensia Cavalcade enters, create two Weapon tokens. (They're Equipment artifacts with “Equipped creature gets +1/+1” and equip {2}.)

Target creature you don't control fights target creature you control, then fights up to one other target creature you don't control.

At the beginning of your upkeep, you lose 1 life and create a 1/1 white Soldier creature token with melee. (Whenever that creature attacks, it gets +1/+1 until end of turn for each opponent you attacked this combat.)

{W}: Gorran Explorer gains lifelink until end of turn.

Planar Alignment enters tapped.
{T}: Add {C}.
{6}, {T}, Exile Planar Alignment: Search your library for a card, put it into your hand, then shuffle.

When Screams from the Deep enters, exile up to one target monocolored permanent.
As long as an opponent owns three or more cards in exile, you may have Screams from the Deep assign its combat damage as though it weren't blocked.
Evoke {5} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

Whenever Hero's Henchman attacks, another target creature you control gets +1/+1 until end of turn.

When Dunecrest Pariah enters, you may search your library for a basic land or Desert card, reveal it, put it into your hand, then shuffle.
{T}, Sacrifice Dunecrest Pariah: You may put a land card from your hand onto the battlefield tapped.

Gain control of target creature if its power is less than or equal to the number of cards in your hand.
Quickdraw {4}{U}{U} (When a creature you control blocks or becomes blocked, you may cast this spell for {4}{U}{U}.)

Death knell — All creatures get -1/-1 until end of turn. (As a creature you control dies, trigger one death knell of that creature or another permanent you control.)
{B}, Sacrifice a creature: Choose a card in your graveyard with mana value less than the sacrificed creature's mana value. You may cast it without paying its mana cost.

Flying
Whenever Elite of Mahara attacks, exile up to two target cards from graveyards. For each permanent card exiled this way, put a +1/+1 counter on Elite of Mahara. For each nonpermanent card exiled this way, each opponent loses 1 life and you gain 1 life.