msem-instigator

Enchant opponent
Whenever enchanted opponent casts a spell, you may reveal cards from the top of your library until you reveal a nonland card that costs less. Exile that card, and put the rest on the bottom in a random order. You may play the exiled card until the end of your next turn.

Scry 1.
Draw a card.

Choose a permanent type. Permanents you control of that type gain hexproof until end of turn.
Spell mastery — If there are two or more instant and/or sorcery cards in your graveyard, permanents you control gain hexproof until end of turn instead.

Target attacking creature gets +3/+1 and gains trample until end of turn. (Then exile this card. You may cast the creature later from exile.)

Target opponent sacrifices half the permanents they control, rounded down.

When Duchess Odelia VII enters, search your library for a nonland permanent card with mana value 1 or less, reveal it, put it into your hand, then shuffle.

Whenever you cast an enchantment spell, you draw a card and you lose 1 life.
Whenever one or more counters are put on an enchantment you control, you gain 1 life and each opponent loses 1 life.

Reach
{1}, Sacrifice a nonland permanent: Imposing Manticore deals 1 damage to each opponent.

As The Mistake enters, choose a card name.
Activated abilities of sources with the chosen name can't be activated unless they're mana abilities.
Unveil {5} ({5}: Transform this. Unveil only as a sorcery.)

Exile target nonland permanent. Its controller gains 5 life.

Adorned — Mercenary Lancer gets +2/+2 as long as it's equipped and/or enchanted.

When Overgrowth Guardian enters, germinate. (Put a +1/+1 counter on a creature or create a 1/1 green Saproling creature token.)

As an additional cost to cast this spell, sacrifice an artifact or enchantment.
You draw three cards and you lose 3 life.

Flash
When Odaya Magistrate enters, you may counter target noncreature spell.

First strike (This creature deals combat damage before creatures without first strike.)

Colorless creatures you control get +1/+1.

Flying
Whenever you cast a spell from your graveyard, return Unliving Swarm from your graveyard to your hand.

Sculpted Observatory enters tapped.
{T}: Add {W} or {U}.
{1}, {T}: Add one mana of any color.

{1}, Tap an untapped creature you control: Leaping Dancer gets +0/+1 and gains flying until end of turn. Then if you've activated this ability three or more times this turn, transform Leaping Dancer.

{2}{R}, Sacrifice a creature: Target creature can't block this turn.

Target creature gets -4/-0 until end of turn.
Flashback {U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

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.

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Whenever another noncreature source deals damage to a creature or player, you may have Hav'za, Itavan Warchief deal half that damage, rounded up, to any target.

As an additional cost to cast this spell, you may sacrifice three artifacts.
Search your library for an artifact card, reveal it, put it into your hand, then shuffle. If you sacrificed three artifacts as you cast this spell, you may put a noncreature artifact card from your hand onto the battlefield.

When Arcor-Staff Adherent enters, you may remove all -1/-1 counters from target creature.