msem-instigator

You may cast target instant or sorcery card from your graveyard this turn. If that spell would be put into your graveyard, exile it instead.

Sacrifice Chromeleon: Add one mana of any color. Scry 1.

Clockwork Gaucho enters with a +1/+1 counter on it.
Other artifact creatures you control get +1/+1 for each +1/+1 counter on Clockwork Gaucho.
{T}: Put a +1/+1 counter on Clockwork Gaucho.

Spells your opponents cast that target Danithra Muckbruiser cost {2} more to cast.
Danithra Muckbruiser gets +X/+X, where X is the number of cards in your graveyard minus seven. (If there are fewer than seven, it gets +0/+0.)

Flash
When Dehmi, Origin Seeker enters, counter target spell an opponent controls unless that spell's controller has you create X 1/1 red Elemental creature tokens, where X is that spell's mana value.

As long as you control no other Humans, Lone Survivor gets +2/+2 and has “Noncreature spells cost {1} more to cast.”

First mate—Each nonland card in your starting deck has “destroy,” “die,” “graveyard,” and/or “mill” in its printed rules text. (If this card outside the game is your chosen first mate, you may swap it with a card in your opening hand.)
Deathtouch
When Marisa enters, if it was cast, you may put target permanent card from a graveyard onto the battlefield under your control.

Prismatic — Whenever you cast a multicolored spell, create a 1/1 blue Bird creature token with flying. It gains haste until end of turn.
Whenever three or more creatures you control deal combat damage to a player, draw a card.

Whenever you cast a noncreature spell, you may pay {U}. If you do or the spell was cast from your graveyard, draw a card.