Getting

Nadaar, Selfless Paladin

Vigilance
Whenever Nadaar, Selfless Paladin enters or attacks, venture into the dungeon. (Enter the first room or advance to the next room.)
Other creatures you control get +1/+1 as long as you've completed a dungeon.

Exchange

Lolth, Spider Queen

Whenever a creature you control dies, put a loyalty counter on Lolth, Spider Queen.
0: You draw a card and you lose 1 life.
−3: Create two 2/1 black Spider creature tokens with menace and reach.
−8: You get an emblem with "Whenever an opponent is dealt combat damage by one or more creatures you control, if that player lost less than 8 life this turn, they lose life equal to the difference."

Flip

Precipitous Drop

Enchant creature
When Precipitous Drop enters, venture into the dungeon. (Enter the first room or advance to the next room.)
Enchanted creature gets -2/-2. It gets -5/-5 instead as long as you've completed a dungeon.

Primal Vigor

If one or more tokens would be created, twice that many of those tokens are created instead.
If one or more +1/+1 counters would be put on a creature, twice that many +1/+1 counters are put on that creature instead.

Temple of the Dragon Queen

As Temple of the Dragon Queen enters, you may reveal a Dragon card from your hand. Temple of the Dragon Queen enters tapped unless you revealed a Dragon card this way or you control a Dragon.
As Temple of the Dragon Queen enters, choose a color.
{T}: Add one mana of the chosen color.

Scion of Halaster

Commander creatures you own have "The first time you would draw a card each turn, instead look at the top two cards of your library. Put one of them into your graveyard and the other back on top of your library. Then draw a card."

Varis, Silverymoon Ranger

Reach, ward {1}
Whenever you cast a creature or planeswalker spell, venture into the dungeon. This ability triggers only once each turn. (To venture into the dungeon, enter the first room or advance to the next room.)
Whenever you complete a dungeon, create a 2/2 green Wolf creature token.

Assemble the Rank and Vile

Hidden agenda (Start the game with this conspiracy face down in the command zone and secretly choose a card name. You may turn this conspiracy face up any time and reveal that name.)
Creatures you control with the chosen name have "When this creature dies, you may pay {B}. If you do, create a tapped 2/2 black Zombie creature token."

Boros Guildgate

Boros Guildgate enters tapped.
{T}: Add {R} or {W}.

Zalto, Fire Giant Duke

Trample
Whenever Zalto, Fire Giant Duke is dealt damage, venture into the dungeon. (Enter the first room or advance to the next room.)

Gruul Guildgate

Gruul Guildgate enters tapped.
{T}: Add {R} or {G}.

Ancient Bronze Dragon

Flying
Whenever Ancient Bronze Dragon deals combat damage to a player, roll a d20. When you do, put X +1/+1 counters on each of up to two target creatures, where X is the result.

Dimir Guildgate

Dimir Guildgate enters tapped.
{T}: Add {U} or {B}.

Gateway Plaza

Gateway Plaza enters tapped.
When Gateway Plaza enters, sacrifice it unless you pay {1}.
{T}: Add one mana of any color.

Advantageous Proclamation

(Start the game with this conspiracy face up in the command zone.)
Your minimum deck size is reduced by five.

Cloister Gargoyle

When Cloister Gargoyle enters, venture into the dungeon. (Enter the first room or advance to the next room.)
As long as you've completed a dungeon, Cloister Gargoyle gets +3/+0 and has flying.

Azorius Guildgate

Azorius Guildgate enters tapped.
{T}: Add {W} or {U}.

Crucible of the Spirit Dragon

{T}: Add {C}.
{1}, {T}: Put a storage counter on Crucible of the Spirit Dragon.
{T}, Remove X storage counters from Crucible of the Spirit Dragon: Add X mana in any combination of colors. Spend this mana only to cast Dragon spells or activate abilities of Dragons.

Ancient Silver Dragon

Flying
Whenever Ancient Silver Dragon deals combat damage to a player, roll a d20. Draw cards equal to the result. You have no maximum hand size for the rest of the game.

Barrowin of Clan Undurr

When Barrowin of Clan Undurr enters, venture into the dungeon. (Enter the first room or advance to the next room.)
Whenever Barrowin of Clan Undurr attacks, return up to one creature card with mana value 3 or less from your graveyard to the battlefield if you've completed a dungeon.

Agent of the Shadow Thieves

Commander creatures you own have "Whenever this creature attacks a player, if no opponent has more life than that player, put a +1/+1 counter on this creature. It gains deathtouch and indestructible until end of turn."

Manor Gate

Manor Gate enters tapped.
As Manor Gate enters, choose a color other than green.
{T}: Add {G} or one mana of the chosen color.

Rakdos Guildgate

Rakdos Guildgate enters tapped.
{T}: Add {B} or {R}.

Simic Guildgate

Simic Guildgate enters tapped.
{T}: Add {G} or {U}.

Cloakwood Hermit

Commander creatures you own have "At the beginning of your end step, if a creature card was put into your graveyard from anywhere this turn, create two tapped 1/1 green Squirrel creature tokens."

Icingdeath, Frost Tyrant

Flying, vigilance
When Icingdeath, Frost Tyrant dies, create Icingdeath, Frost Tongue, a legendary white Equipment artifact token with "Equipped creature gets +2/+0," "Whenever equipped creature attacks, tap target creature defending player controls," and equip {2}.

Izzet Guildgate

Izzet Guildgate enters tapped.
{T}: Add {U} or {R}.

Crash Through

Creatures you control gain trample until end of turn. (A creature with trample can deal excess combat damage to the player or planeswalker it's attacking.)
Draw a card.

Oswald Fiddlebender

Magical Tinkering — {W}, {T}, Sacrifice an artifact: Search your library for an artifact card with mana value equal to 1 plus the sacrificed artifact's mana value, put it onto the battlefield, then shuffle. Activate only as a sorcery.

Drizzt Do'Urden

Double strike
When Drizzt Do'Urden enters, create Guenhwyvar, a legendary 4/1 green Cat creature token with trample.
Whenever a creature dies, if it had power greater than Drizzt's power, put a number of +1/+1 counters on Drizzt equal to the difference.

Old Gnawbone

Flying
Whenever a creature you control deals combat damage to a player, create that many Treasure tokens.

Haven of the Spirit Dragon

{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a Dragon creature spell.
{2}, {T}, Sacrifice Haven of the Spirit Dragon: Return target Dragon creature card or Ugin planeswalker card from your graveyard to your hand.

Golgari Guildgate

Golgari Guildgate enters tapped.
{T}: Add {B} or {G}.

Whir of Invention

Improvise (Your artifacts can help cast this spell. Each artifact you tap after you're done activating mana abilities pays for {1}.)
Search your library for an artifact card with mana value X or less, put it onto the battlefield, then shuffle.

Pixie Guide

Flying
Grant an Advantage — If you would roll one or more dice, instead roll that many dice plus one and ignore the lowest roll.

Selesnya Guildgate

Selesnya Guildgate enters tapped.
{T}: Add {G} or {W}.

Xorn

If you would create one or more Treasure tokens, instead create those tokens plus an additional Treasure token.

Veteran Soldier

Commander creatures you own have "Whenever this creature attacks a player, if no opponent has more life than that player, for each opponent, create a 1/1 white Soldier creature token that's tapped and attacking that opponent."

Karlach, Fury of Avernus

Whenever you attack, if it's the first combat phase of the turn, untap all attacking creatures. They gain first strike until end of turn. After this phase, there is an additional combat phase.
Choose a Background (You can have a Background as a second commander.)

Fates' Reversal

Return up to one target creature card from your graveyard to your hand. Venture into the dungeon. (Enter the first room or advance to the next room.)

Incendiary Dissent

Hidden agenda (Start the game with this conspiracy face down in the command zone and secretly choose a card name. You may turn this conspiracy face up any time and reveal that name.)
Creatures you control with the chosen name have "{R}: This creature gets +1/+0 until end of turn."