msem-instigator

Gain control of target creature until end of turn. Untap that creature. It gains haste until end of turn.

Spirited (When this creature enters, you may activate one of its activated abilities without paying its cost.)
{2}{W}: Target creature gains vigilance until end of turn.

Flash
Trample

{B}, {T}: Post a bounty on target permanent. (Put a bounty counter on that permanent. It has “When this permanent is put into a graveyard from the battlefield, each opponent draws a card” as long as it has a bounty counter on it.)
{B}, {T}, Pay 2 life: Destroy target creature with a bounty counter on it.

As long as you control another creature with flying, Wild Skycub has flying.

When Warping Relic enters or is put into a graveyard from the battlefield, choose one —
• Draw two cards, then discard a card.
• Return another target nonland permanent to its owner's hand.
• Choose any number of target creatures. Switch their power and toughness until end of turn.

Whenever a creature an opponent controls becomes tapped, put a +1/+1 counter on Chalkira Duelist.

Enchant creature
When Hannaru's Courage enters, create a 1/1 white Soldier creature token with vigilance.
Enchanted creature gets +1/+1 and has vigilance.

Whenever Single-Minded Mob becomes untapped, it gets +2/+2 until end of turn.

At the beginning of your upkeep, each player draws a card.

Flying
{1}{W/U}{W/U}: Creatures you control gain flying until end of turn if another creature you control has flying. The same is true for first strike, double strike, deathtouch, haste, indestructible, lifelink, menace, reach, trample, and vigilance.

Flash
Enchant artifact or creature
Enchanted permanent is an artifact with “{T}: Draw a card, then discard a card” and loses all other card types and abilities.

{T}, Exert Bestower of Princely Sin: You may sacrifice another creature. If you do, target opponent may sacrifice a permanent that shares a card type with it. If they don't, that player loses 1 life and you draw a card. Repeat this process for artifact, enchantment, land, and planeswalker. Activate only as a sorcery.

When Fungal Whomper enters, you gain 4 life.
When Fungal Whomper leaves the battlefield, germinate four times. (To germinate, put a +1/+1 counter on a creature or create a 1/1 green Saproling creature token.)

Target permanent gains hexproof and indestructible until end of turn. Scry 1.

Tithe (As you cast this spell, you may tap three artifacts and/or creatures you control.)
You gain 6 life. If this spell's tithe was paid, draw a card.

You may cast Elemental spells as though they had flash this turn.
Whenever you cast an Elemental spell this turn, draw a card.

Artifact creatures you control get +1/+1.
{U}{R}, Sacrifice an artifact: Create a 1/1 colorless Servo artifact creature token.

When Graygulch Howler dies, you gain 1 life for each Spirit you control.

{2}: Other creatures you control get +1/+0 until end of turn.
Whenever Sun-Crowned Flagship attacks, each attacking creature you control gains trample until end of turn.
Crew 7 (Tap any number of creatures you control with total power 7 or greater: This Vehicle becomes an artifact creature until end of turn.)

Other Rogues you control have menace.
{2}{U}: Target blocking creature gets -1/-0 until end of turn.

When Sandwurm's Might enters, you may have target creature you control fight target creature you don't control.
Each creature you control enters with an additional +1/+1 counter on it.

Whenever you cast a noncreature spell, put a quest counter on Gate to the Beyond.
At the beginning of your upkeep, if there are three or more quest counters on Gate to the Beyond, you draw a card and you lose 1 life. Then if there are six or more quest counters on it, each opponent loses 2 life.

Opera House enters tapped.
When Opera House enters, add one mana of any color.
{T}, Sacrifice Opera House: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.