Neurok Spy

This creature can't be blocked as long as defending player controls an artifact.

Guild Thief

Whenever this creature deals combat damage to a player, put a +1/+1 counter on it.
Cunning Action — {3}{U}: This creature can't be blocked this turn.

Merfolk Spy

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
Whenever this creature deals combat damage to a player, that player reveals a card at random from their hand.

Krydle of Baldur's Gate

Whenever Krydle deals combat damage to a player, that player loses 1 life and mills a card, then you gain 1 life and scry 1.
Whenever you attack, you may pay {2}. If you do, target creature can't be blocked this turn.

Vampire Cutthroat

Skulk (This creature can't be blocked by creatures with greater power.)
Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Imoen, Mystic Trickster

Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)
At the beginning of your end step, if you have the initiative, draw a card. Draw another card if you've completed a dungeon.
Choose a Background (You can have a Background as a second commander.)

Shortcut Seeker

Whenever this creature deals combat damage to a player, venture into the dungeon. (Enter the first room or advance to the next room.)

Revel Ruiner

Menace (This creature can't be blocked except by two or more creatures.)
When this creature enters, it connives. (Draw a card, then discard a card. If you discarded a nonland card, put a +1/+1 counter on this creature.)

Marang River Prowler

This creature can't block and can't be blocked.
You may cast this card from your graveyard as long as you control a black or green permanent.

Invisible Stalker

Hexproof (This creature can't be the target of spells or abilities your opponents control.)
This creature can't be blocked.

Varragoth, Bloodsky Sire

Deathtouch
Boast — {1}{B}: Target player searches their library for a card, then shuffles and puts that card on top. (Activate only if this creature attacked this turn and only once each turn.)

Safana, Calimport Cutthroat

Menace
At the beginning of your end step, if you have the initiative, create a Treasure token. Create three of those tokens instead if you've completed a dungeon.
Choose a Background (You can have a Background as a second commander.)

Prickly Boggart

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)

Infiltrator il-Kor

Shadow (This creature can block or be blocked by only creatures with shadow.)
Suspend 2—{1}{U} (Rather than cast this card from your hand, you may pay {1}{U} and exile it with two time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost. It has haste.)

Canal Courier

When this creature enters, you become the monarch.
Whenever this creature and another creature attack different players, this creature can't be blocked this combat.

Looter il-Kor

Shadow (This creature can block or be blocked by only creatures with shadow.)
Whenever this creature deals damage to an opponent, draw a card, then discard a card.

Slither Blade

Yuan-Ti Malison

This creature can't be blocked as long as it's attacking alone.
Whenever this creature deals combat damage to a player, venture into the dungeon. (Enter the first room or advance to the next room.)

Deathcult Rogue

This creature can't be blocked except by Rogues.

Rilsa Rael, Kingpin

Deathtouch
When Rilsa Rael enters, you take the initiative.
Whenever you attack, target attacking creature gains deathtouch until end of turn. If you've completed a dungeon, that creature also gets +5/+0 and gains first strike and menace until end of turn.

Yuan-Ti Fang-Blade

Deathtouch
Whenever this creature deals combat damage to a player, venture into the dungeon. (Enter the first room or advance to the next room.)

Aarakocra Sneak

Flying
When this creature enters, you take the initiative.

Anowon, the Ruin Thief

Other Rogues you control get +1/+1.
Whenever one or more Rogues you control deal combat damage to a player, that player mills a card for each 1 damage dealt to them. If the player mills at least one creature card this way, you draw a card. (To mill a card, a player puts the top card of their library into their graveyard.)

Thada Adel, Acquisitor

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
Whenever Thada Adel deals combat damage to a player, search that player's library for an artifact card and exile it. Then that player shuffles. Until end of turn, you may play that card.

Eloise, Nephalia Sleuth

Whenever another creature you control dies, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")
Whenever you sacrifice a token, surveil 1. (Look at the top card of your library. You may put that card into your graveyard.)

Expedition Lookout

Defender
As long as an opponent has eight or more cards in their graveyard, this creature can attack as though it didn't have defender and it can't be blocked.

Sygg, River Cutthroat

At the beginning of each end step, if an opponent lost 3 or more life this turn, you may draw a card. (Damage causes loss of life.)

Grim Hireling

Whenever one or more creatures you control deal combat damage to a player, create two Treasure tokens.
{B}, Sacrifice X Treasures: Target creature gets -X/-X until end of turn. Activate only as a sorcery.

Butch DeLoria, Tunnel Snake

Menace (This creature can't be blocked except by two or more creatures.)
Tunnel Snakes Rule! — Whenever Butch DeLoria attacks, it gets +1/+1 until end of turn for each other Rogue and/or Snake you control.
{1}{B}: Put a menace counter on another target creature. It becomes a Rogue in addition to its other types.