msem-instigator

Each player puts the bottom five cards of their library into their graveyard.
Fuse (You may cast one or both halves of this card from your hand.)

Enchant creature or land
Whenever enchanted permanent becomes tapped for the first time each turn, it explores. (Reveal the top card of your library. Put that card into your hand if it's a land. Otherwise, put a +1/+1 counter on that creature, then put the card back or put it into your graveyard.)

When Lay Bare Ambitions enters, if it was cast, target opponent reveals their hand. Choose a nonland card from it. That player discards that card.
If a spell or ability an opponent controls would cause them to draw one or more cards, instead sacrifice Lay Bare Ambitions and they skip those draws.

{T}: Add {C}.
{T}, Exile two cards from your graveyard: Add {U} or {B}.

Flying
Whenever Haunter of the Deadlands attacks, Spirit creatures you control get +1/+1 until end of turn.

Flying
Disgraced 4 (This enters with four -1/-1 counters. Whenever it deals combat damage to a player, remove all -1/-1 counters from it.)
Whenever you put one or more -1/-1 counters on Forgotten Tyrant, it deals that much damage to any target.

Until end of turn, target creature gets +2/+2, then an additional +2/+2 for each card and token merged with it.

This spell costs {2} less to cast for each face-down creature you control.
Flying

Rammanethi Hydroshaper gets +1/+1 as long as you control an Island.
{2}{U}: Target creature blocking or blocked by Rammanethi Hydroshaper gets -1/-0 until end of turn.

Return target creature card with mana value 3 or less from your graveyard to the battlefield. If its mana value is less than 3, you gain life equal to the difference.

You may cast cast up to two target instant and/or sorcery cards with total mana value 6 or less from your graveyard without paying their mana costs. If a spell cast this way would be put into your graveyard, exile it instead.
Exile Pointer Churn.

Vigilance
When Paired Pathfinders enters, if three or more colors were spent to cast it, create a 1/1 colorless Servo artifact creature token.

Trample
When Saddlesaur Guide enters, create a green Aura enchantment token named Hefty Load attached to target creature. The token has enchant creature and “Enchanted creature gets +2/+2 and has trample.”

Flying
When Krothuss, Abyssal Terror dies, return all creatures to their owners' hands except for Krakens, Leviathans, Octopuses, and Serpents.
Foreshadow {6}{U}{U} (You may cast this spell for its foreshadow cost. If you do, also trigger its “dies” abilities when it enters.)

Whenever another creature you control dies, creatures you control get +1/+0 until end of turn.
Whenever this creature attacks, you may pay {2}{R} and sacrifice another creature. If you do, this creature gains menace until end of turn.

Menace
Whenever Issbarren Creeper deals combat damage to a player, draw a card, then discard a card.

As an additional cost to cast this spell, sacrifice a permanent.
Exile target creature.

Flying
At the beginning of your end step, untap target permanent you control.

Flying
Creatures you don't control have “{T}: This creature fights Ontarachie Apex. Activate only as a sorcery.”

When Silencing Guardian enters, you may have target creature get -1/-1 until end of turn.

Whenever you detain a permanent, you gain life equal to that permanent's mana value.

Spells you cast during combat cost {1} less to cast.
Spells your opponents cast during combat cost {1} more to cast.

Equipped creature gets +2/+2 and has flying.
At the beginning of your upkeep, if Devised Battlesuit is attached to a non-Artificer creature, sacrifice Devised Battlesuit.
Equip {4}

Equipped creature gets +1/+1.
Sacrifice Forceglow Shield: Prevent all damage a source of your choice would deal to equipped creature this turn.
Equip {2}

Distorted (This creature can be blocked by tapped creatures but not untapped creatures.)
During each of your turns, you may cast an instant or sorcery spell from your graveyard. If that spell would be put into your graveyard, exile it instead.
Whenever Aurora, Soulweaver attacks, untap any number of target creatures.