msem-instigator

Equipped creature gets +1/+0 for each artifact you control.
As long as you control three or more artifacts, equipped creature has flying and haste.
Equip {3}

Cast a copy of target creature or Revelation card in your graveyard without paying its mana cost. If a Revelation is cast this way, it enters as a Horror creature after it resolves.
Exile Wish to See.

Gain control of target creature until end of turn.
Coalesce {6}{U}{B} (You may cast this from your graveyard for {6}{U}{B}. If you do, it enters as a Horror creature after it resolves. Exile it if it would leave the battlefield or not resolve.)
As long as Mortal Whims Falter is on the battlefield, you can't lose control of permanents.

When Ankulith Shard enters, draw a card.
{1}, {T}: Add one mana of any color.

At the beginning of each player's draw step, that player draws an additional card.
Spells cost {1} less to cast.
Players may spend mana as though it were mana of any color.

{2}, {T}: You gain 5 life. Shuffle Elixir of Immortality and your graveyard into their owner's library.

Guidestone enters tapped.
{T}: Add {C}.
{2}, Sacrifice Guidestone: Draw a card.

Whenever you cast a noncreature spell, you may put a progress counter on Hellbent Speed.
[PROGRESS 2+] Noncreature 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.
[PROGRESS 6+] Whenever you cast a noncreature spell, draw a card.

Multipurpose Mannequin gets +1/+1 for each permanent attached to it.

When Nidohagane Warfans enters, if it's not a token, create a token that's a copy of it.
Equipped creature gets +1/+0.
Equip {1}

{1}, {T}: Exile target card from a graveyard. Scry 1.
{T}, Exile Soul Gate: Exile all graveyards.

When Stonefall Golem leaves the battlefield, destroy target permanent.

Untap all other artifacts you control during each other player's untap step.
{T}: Untap another target permanent.

({T}: Add {R}.)
Bloodriver enters tapped.
When Bloodriver enters, target creature you control gains haste until end of turn.

({T}: Add {W} or {U}.)
Bustling Harbor enters tapped.
Cycling {2} ({2}, Discard this card: Draw a card.)

({T}: Add {U}.)
Cloudbank enters tapped.
When Cloudbank enters, target creature gains flying until end of turn.

({T}: Add {B}.)
Corpsebed enters tapped.
When Corpsebed enters, exile up to two target cards from graveyards.

({T}: Add {W} or {B}.)
Dreary Township enters tapped.
Cycling {2} ({2}, Discard this card: Draw a card.)

({T}: Add {R} or {G}.)
Glittering Grove enters tapped.
Cycling {2} ({2}, Discard this card: Draw a card.)

The Last Sacred Gate enters tapped.
While you're searching your library, you may play The Last Sacred Gate from your library. (You may only do so during your turn and if you have a land play remaining.)
{T}: Add {C}.

({T}: Add {G} or {U}.)
Monsoon Lagoon enters tapped.
Cycling {2} ({2}, Discard this card: Draw a card.)

({T}: Add {W}.)
Sunstage enters tapped.
When Sunstage enters, creatures you control get +0/+1 until end of turn.

({T}: Add {B} or {R}.)
Urban Wastelands enters tapped.
Cycling {2} ({2}, Discard this card: Draw a card.)

If an opponent controls more lands than you, search your library for a Plains card. If an opponent controls more creatures than you, search your library for a creature card with mana value 2 or less. Reveal those cards, put them into your hand, then shuffle.