msem-instigator

Flying
Whenever Seer of Clear Skies or another creature you control with flying attacks, that creature gets +1/+1 until end of turn.

Whenever Shianne's Guardian or another creature you control enters, you may pay {1}{R}{G}. When you do, that creature deals damage equal to its power to any target.

Flying
When Shilgengar's Harvester enters, each opponent discards a card and loses 2 life.

If you control seven or more creatures, you may cast Sociable Giant without paying its mana cost.
Trample

Flying
Whenever another Wizard you control enters, you draw a card and each opponent discards a card.
Revive {5}{U}{B} ({5}{U}{B}, Exile this card from your graveyard: Create a token that's a copy of it except it has no mana cost. Revive only as a sorcery.)

Creatures you control get +2/+0 until end of turn.
Whenever an opponent fails a trial, if Combatant Conflagration is in your graveyard, target creature you control gets +2/+0 until end of turn.

Target creature gets +X/+0 and gains trample until end of turn.

When Thunderstep Ved enters, it deals 1 damage to any target.

Flying
Falkenrath Ordainer has lifelink as long as you control a token.

Engorge (As this enters, mill three cards, then exile a card from among the milled cards.)
When Bloodchill Risen enters, if it engorged an instant card, return target creature to its owner's hand.

When Voliv Ritualist enters, choose two different basic land types. Create a tapped colorless land token that's the chosen types. When Voliv Ritualist is no longer on the battlefield, sacrifice a land.

Return up to one target creature card and up to one target land card from your graveyard to your hand.

Flying
When Ageless Lorekeeper enters, you may discard your hand. When you do, draw three cards.

Puzzlebox (Begin the game with this and another card you own from outside the game in the command zone, locked. That card is face down until you unlock this.)
When the fourth spell of a turn is cast, you may unlock Mirror Cipher. If the revealed card is an instant or sorcery card, cast it without paying its mana cost and copy it. You may choose new targets for the copy.

Other Hounds you control get +1/+1.

Double strike
Concord — Pristine Duelist gets +2/+1 as long as there are four or more card types among permanents you control.

At the beginning of each end step, if a creature died this turn, you may put a +1/+1 counter on target creature you control.

Whenever Roving Dreadnought attacks, you may salvage a card that was put into your graveyard this turn. (Exile one from your graveyard until this creature leaves the battlefield. Whenever this creature deals combat damage to a player, put a card it salvaged into your hand.)

Once each turn, when a creature you control enters, you may draw a card if its power is greater than each other creature's power.

Prowess, trample
During your turn, each instant and sorcery card in your graveyard has flashback. The flashback cost is equal to that card's mana cost plus “Pay X life, where X is this card's mana value.”

Flying
Desecrate (When this creature enters, you may sacrifice an artifact or land.)
When Liege of Luxury desecrates a permanent, target player reveals their hand. You choose a card from it and exile it. You may cast that card for as long as it remains exiled, and you may spend mana as though it were mana of any type to cast that spell.

Enchant opponent
At the beginning of enchanted player's upkeep, they choose one that hasn't been chosen yet —
• They discard three cards.
• They sacrifice three nonland permanents.
• You transform Enrapturing Grudge.
If Enrapturing Grudge would be put into a graveyard from anywhere, exile it instead.

{2}, {T}, Sacrifice Old Map: Search your library for a basic land card, put it onto the battlefield, then shuffle.

Trample
Engage (This creature must be blocked each combat if able.)
When Lion's Vanguard enters, creatures you control get +3/+3 and gain trample and haste until end of turn.