msem-instigator

{T}: Add {C}{C}. Spend this mana only to cast spells with mana value 5 or greater.

Flash
When Frontier Paragon enters, untap all creatures you control.

As Theodore Harper, Head Librarian enters, choose Fact or Fiction.
• Fact — Permanent spells you cast cost {1} less to cast. This effect can't reduce the amount of mana a spell costs to cast to less than one mana.
• Fiction — When Theodore Harper enters, return a permanent card from your graveyard to your hand.

Lifelink
{B}, Sacrifice Lostrite Evoker: Add {B}{B}{B}.

Dekinn, Depths Spirit can't attack or block unless a player has lost 3 or more life this turn.
At the beginning of each player's upkeep, that player may create a Mountain token. If they do, Dekinn deals 3 damage to them.
When Dekinn dies or is put into exile from the battlefield, you may put him into his owner's library third from the top.

Creatures you control get +1/+1 until end of turn.
Artifact creatures and Elementals you control get +1/+1 until end of turn.

Draw two cards. Each opponent draws a card.

Choose target card in a graveyard other than a basic land card. Search its owner's graveyard, hand, and library for any number of cards with the same name as that card and exile them. Then that player shuffles.
Scry 1.

{1}, Sacrifice a creature: Each opponent loses 1 life and you gain 1 life.

Enchant creature
Enchanted creature gets -3/-3.

Reach
Whenever Elemental of Vengeance is dealt damage, it deals damage equal to its power to any target.

Advance {3} (Cast this for {3} to advance it as it enters. {3}: Advance this as a sorcery.)
Whenever Wastes Scrambler advances, put your choice of a +1/+1, first strike, menace, trample, or vigilance counter on it. If {R}{W}{B} was spent to advance it, repeat this process twice.
Crew 1

Whenever you investigate for the first time each turn, investigate an additional time.
{T}, Sacrifice an artifact: Cadalon Inspector deals 2 damage to any target.

Archive 3 (As this enters, shuffle the top three cards of your main library into a new face up library. Sacrifice this after the archived library is empty.)
Whenever you draw a card from the archived library, put the top card of your main library on the bottom of the archived library.
{R}: Exchange a card from the archived library with a card from your hand.

All creatures get -4/-4 until end of turn. If a creature would die this turn, exile it instead.

Assault {1}{G} (Whenever this attacks, if it has no +1/+1 counters on it, you may pay its assault cost to put a +1/+1 counter on it.)
When Caprin Outlander assaults, you gain 3 life.

Enchant creature
When Claustrophobia enters, tap enchanted creature.
Enchanted creature doesn't untap during its controller's untap step.

Destroy target creature.

Enchant creature
Enchanted creature gets +2/+2 and has vigilance.
Sacrifice Spirit Guidance: Exile enchanted creature, then return it to the battlefield under its owner's control.

Renown 2 (When this creature deals combat damage to a player, if it isn't renowned, put two +1/+1 counters on it and it becomes renowned.)
Whenever Fortunate Exorcist attacks, if it's renowned, exile up to one target card from defending player's graveyard.

This spell costs {1} less to cast for each other card in your hand.
If you have fewer than seven cards in hand, draw cards equal to the difference.

{T}: Each of two other target permanents you control that share a card type become a copy of the other until end of turn.

{2/R}{2/R}: Churning Rough-Roller gets +1/+1 and gains double strike until end of turn.

Until end of turn, creatures you control get +1/+1 and gain prowess. If there are two or more instant and/or sorcery cards in your graveyard, draw a card.

When Voldaren Crypt-Guard enters, create a Weapon token. (It's an Equipment artifact with “Equipped creature gets +1/+1” and equip {2}.)