msem-instigator

Spells you cast that target Risti Operative cost {1} less to cast.
Abilities you activate that target Risti Operative cost {1} less to activate.

Artifact and enchantment spells you cast cost {1} less to cast.
Whenever Risti Salvager attacks, rediscover an artifact or enchantment card. (Look at the top card of your library. You may reveal it and put it into your hand if it's an artifact or enchantment card. Otherwise, put it back or into your graveyard.)

Vigilance
{3}{G}, {T}: Target creature you control fights target creature you don't control.

Choose one —
• Target player sacrifices a creature.
• Target player reveals their hand. Choose a creature card from it. They discard that card.

Reach
When Risti Watchkeeper enters, rediscover a creature card. (Look at the top card of your library. You may reveal it and put it into your hand if it's a creature card. Otherwise, put it back or into your graveyard.)

{T}: Add {C}.
{1}: Risti Workshop becomes a creature in addition to its other types until end of turn.
When Risti Workshop deals combat damage to an opponent, you may sacrifice it. If you do, search your library for a basic land card, put it onto the battlefield, then shuffle.

Until end of turn, target creature gains deathtouch and “When this creature dies, return it to the battlefield tapped under its owner's control with a +1/+1 counter on it.”

Target creature gets -4/-4 until end of turn. When it dies this turn, create two 1/1 black Worm creature tokens.

At the beginning of your upkeep, you lose 1 life, then investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)
Whenever you sacrifice a permanent, each opponent loses 1 life.

At the beginning of your upkeep, if an opponent has more life than you, create a 4/4 red Elemental creature token with haste and “Creatures blocking this creature have winnow.” (Damage dealt to a creature with winnow causes its controller to lose that much life.)

Bloodprice {B} (You may cast this card by sacrificing a creature and paying its bloodprice.)
Destroy target creature.

As an additional cost to cast this spell, sacrifice a noncreature permanent.
Search your library for a creature card with mana value equal to 1 plus the sacrificed permanent's mana value, put it onto the battlefield, then shuffle.

When Ritesinger Shaman dies, each player discards a card.

As Ritual Preparations enters, choose a color.
You don't lose unspent mana of the chosen color as steps and phases end.

As an additional cost to cast this spell, put two -1/-1 counters on a creature you control.
Draw two cards.

Bloodprice {2}{B} (You may cast this card by sacrificing a creature and paying its bloodprice.)
Create X 2/2 black Demon creature tokens, where X is one plus the number of creatures that died this turn.

Destroy all creatures with mana value 3 or less.

({T}: Add {U} or {R}.)
As Ritzy Parlor enters, you may pay {1}. If you don't, Ritzy Parlor enters tapped.

{T}, Pay 1 life: Add {W}.
{6}{W}{W}{W}, Exile Rius, Temple of the Grandfather from your hand: Target player gains 20 life.

Riv's Safehouse enters tapped.
When Riv's Safehouse enters, you may mill two cards.
{T}: Add {U} or {B}.

Menace
Sabotage — Whenever an opponent or permanent an opponent controls becomes the target of a spell you control, each opponent discards a card.

Flying

When River Miscreants enters, target creature you control can't be blocked this turn.
{2}{U}: Return River Miscreants to its owner's hand. Activate only as a sorcery.

As long as your deck contains only blue and colorless cards, your minimum deck size is reduced by eight.

River's Wrath deals 2 damage to any target. If you've been dealt damage this turn, River's Wrath deals 4 damage instead.