Murder

Dispersal

Each opponent returns a nonland permanent they control with the greatest mana value among permanents they control to its owner's hand, then discards a card.

Discovery

Surveil 2, then draw a card. (To surveil 2, look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)

Discovery // Dispersal

Dimir Strandcatcher

Flying
Whenever you attack, surveil X, where X is the number of opponents being attacked.
At the beginning of each end step, if three or more cards were put into your graveyard from anywhere other than the battlefield this turn, draw a card.

Tithebearer Giant

When this creature enters, you draw a card and you lose 1 life.

Thriving Moor

This land enters tapped. As it enters, choose a color other than black.
{T}: Add {B} or one mana of the chosen color.

Roofstalker Wight

{1}{U}: This creature gains flying until end of turn.

Whisper Agent

Flash
When this creature enters, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Swamp

Dimir Guildgate

This land enters tapped.
{T}: Add {U} or {B}.

Undercover Butler

Whenever this creature attacks the player with the most life or tied for most life, it can't be blocked this turn.

Dimir Aqueduct

This land enters tapped.
When this land enters, return a land you control to its owner's hand.
{T}: Add {U}{B}.

Infest

All creatures get -2/-2 until end of turn.

Masked Blackguard

Flash (You may cast this spell any time you could cast an instant.)
{2}{B}: This creature gets +1/+1 until end of turn.

Thief of Sanity

Flying
Whenever this creature deals combat damage to a player, look at the top three cards of that player's library, exile one of them face down, then put the rest into their graveyard. You may cast that card for as long as it remains exiled, and mana of any type can be spent to cast that spell.

Ribbons of Night

Ribbons of Night deals 4 damage to target creature and you gain 4 life. If {U} was spent to cast this spell, draw a card.

Mausoleum Turnkey

When this creature enters, return target creature card of an opponent's choice from your graveyard to your hand.