msem-instigator

{1}{R}, {T}, Sacrifice an artifact: Elise, Maktali Prodigy deals 2 damage to any target.
{1}{U}, {T}, Sacrifice an artifact: Return target nonland permanent to its owner's hand.
{3}{U}{R}, {T}, Sacrifice three artifacts: Discard your hand, then draw seven cards.

[+1]: Emperor Tzhai deals 1 damage to each creature, planeswalker, and opponent you don't control.
[0]: Target creature can't attack you or Emperor Tzhai until Emperor Tzhai leaves the battlefield.
[–10]: You control target player.

Flash
You may activate Zero's loyalty abilities any time you could cast an instant on your turn and the turn they entered.
[+2]: Destroy up to one target permanent with mana value 4 or greater.
[–2]: You may cast a spell with mana value 5 or less from your hand without paying its mana cost.
[–3]: Search your library for a card and put it into your hand. Shuffle your library.

[+1]: Create a 1/1 red Dragon creature token with flying.
[–1]: Until end of turn, Flynn becomes a copy of target Dragon, except she has haste and indestructible. Her base power and toughness become equal to the number of Dragons you control.
[–3]: You may reveal a Dragon card you own from outside the game and put it into your hand.

Changeling (This card is every creature type.)
As Kalyn, Wildkin Envoy enters, choose up to three non-Human creature types.
Other creatures you control with one or more of the chosen types get +1/+1.
{2}, {T}: Create a 1/1 colorless Shapeshifter creature token with changeling. Activate only outside of combat.

[+2]: Scry 2, then you may draw a card. If you don't, Liactru Stormheart deals 2 damage to any target.
[–4]: Create a 4/4 blue and red Elemental creature token. It gains flying, vigilance, and haste until end of turn.
[–10]: For each player, create a token that's a copy of target permanent that player controls. You get an emblem with “Permanents you control have hexproof.”

[+2]: Create a Vial token. (It's an artifact with “1, Sacrifice this and another permanent: Draw a card. Activate only during your turn.”)
[–3]: Sacrifice another nonland permanent. If you do, destroy target nonland permanent.
[–9]: You get an emblem with “At the beginning of your end step, create Fallen One, a legendary 6/6 black Faerie Angel Avatar creature token with flying.”

Prowess
Whenever you cast your first instant or sorcery spell from your hand during each of your turns, if it doesn't have compose, it gains compose. (Then if you cast this from your hand, exile it and create a Saga token with “r3—You may cast a copy of this card from exile without paying its mana cost.”)

[+1]: Create a 1/1 colorless Elemental creature token. Put a loyalty counter on each planeswalker you control.
[+1]: Untap up to two target permanents.
[–7]: You get an emblem with “Whenever you create a token, draw a card.” Create three 4/4 green Chimera creature tokens.

Whenever you cast a spell that targets, put a loyalty counter on Valeri Kripac and create a 1/1 white Soldier creature token.
[+1]: Add {R}. If you spend this mana on a spell that targets, that spell can't be countered.
[–2]: Exile target instant or sorcery card from your graveyard. You may play it until the end of your next turn. If you do, exile that spell instead of putting it anywhere else.