msem-instigator

Creature spells you cast with power 4 or greater cost {1} less to cast.

Menace
When Rattled Bones dies, forebode. (Create a tapped colorless Omen artifact token with “{T}, Discard a card, Sacrifice this artifact: Draw a card.”)

{W}, {T}: Tap target creature.

Haunted Hovel enters tapped.
{T}: Add {W} or {B}.
When Haunted Hovel enters, you may put a loyalty counter on a planeswalker you control.

Enchant creature
Enchanted creature doesn't untap during its controller's untap step.
Enchanted creature loses all abilities except for mana abilities.

Target opponent may draw two cards. If they do, you draw four cards. Otherwise, you create four 1/1 red Elemental creature tokens.

Target player sacrifices an attacking or blocking creature. Prevent all damage that would be dealt by creatures this turn.

Scry 2, then draw two cards. (Look at the top two cards of your library, then put any number of them on the bottom of your library and the rest on top in any order.)

Equipped creature gets +2/+2.
Equip {3}

Tap another untapped artifact you control: Until end of turn, Glitched Carcass becomes an X/X Construct artifact creature, where X is the mana value of the tapped artifact. Activate only once each turn.

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

Equipped creature gets +1/+1.
At the beginning of combat on your turn, choose flying, first strike, vigilance, trample, or haste. Equipped creature gains that ability until end of turn.
Equip {2}

Sage's Ashes enters tapped.
{T}, Sacrifice Sage's Ashes: Put target card from a graveyard on top of its owner's library.
{3}, Exile Sage's Ashes from your graveyard: Draw a card.

Whenever you draw a card except for the first one you draw in each of your draw steps, each opponent loses 1 life.

{T}: Add {C} and one mana of any color.

Whenever Hurried Scavenger attacks or blocks, you may mill two cards.
Hurried Scavenger gets +4/+4 as long as you have five or more card types among cards in your graveyard.

When Grotto Scarab enters, create two 1/1 green Insect creature tokens for each creature you controlled that died this turn.

Attacking creatures get -3/-0 until end of turn.

Target creature you control has base power and toughness 5/5 and gains trample until end of turn.

This spell can't be countered.
Draw a card.
Reprise {2}{U} (As you cast an instant or sorcery spell, you may exile one card with reprise from your graveyard and pay its reprise cost. If you do, add its effects to that spell.)

Scry 2, then draw two cards. You gain 2 life.
Monument {2}{W}{U} (You may cast this transformed from your graveyard for its monument cost. Exile it if it would leave the battlefield or not resolve.)

Exile the top X cards of target opponent's library. You may play those cards for as long as they remain exiled, and you may spend mana as though it were mana of any color to cast them.

Descended Marsh enters tapped.
{T}: Add {B} or {G}.
Morph {2} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

{B}{G}{U}, Discard a card named Gusma, God of Creation: Gusma gains indestructible and becomes a God creature in addition to its other types.
Whenever Gusma enters or attacks, add {B}{G}{U} and draw a card. You don't lose this mana as steps, phases, and turns end.

{T}: Add {C}.
{3}, {T}, Sacrifice No-Man's Land: Draw a card.