Geier Reach Sanitarium

{T}: Add {C}.
{2}, {T}: Each player draws a card, then discards a card.

Phyrexia's Core

{T}: Add {C}.
{1}, {T}, Sacrifice an artifact: You gain 1 life.

Everglades

This land enters tapped.
When this land enters, sacrifice it unless you return an untapped Swamp you control to its owner's hand.
{T}: Add {C}{B}.

Blighted Fen

{T}: Add {C}.
{4}{B}, {T}, Sacrifice this land: Target opponent sacrifices a creature of their choice.

Encroaching Wastes

{T}: Add {C}.
{4}, {T}, Sacrifice this land: Destroy target nonbasic land.

Terramorphic Expanse

{T}, Sacrifice this land: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Armix, Filigree Thrasher

Whenever Armix attacks, you may discard a card. When you do, target creature defending player controls gets -X/-X until end of turn, where X is the number of artifacts you control plus the number of artifact cards in your graveyard.
Partner (You can have two commanders if both have partner.)

Shrine of the Forsaken Gods

{T}: Add {C}.
{T}: Add {C}{C}. Spend this mana only to cast colorless spells. Activate only if you control seven or more lands.

Sivriss, Nightmare Speaker

{T}, Sacrifice another creature or an artifact: For each opponent, you mill a card, then return that card from your graveyard to your hand unless that player pays 3 life. (To mill a card, put the top card of your library into your graveyard.)
Choose a Background (You can have a Background as a second commander.)

Buried Ruin

{T}: Add {C}.
{2}, {T}, Sacrifice this land: Return target artifact card from your graveyard to your hand.

Tomb of the Spirit Dragon

{T}: Add {C}.
{2}, {T}: You gain 1 life for each colorless creature you control.

Bladegriff Prototype

Flying
Whenever this creature deals combat damage to a player, destroy target nonland permanent of that player's choice that one of your opponents controls.

Aradara Express

Menace
Crew 4 (Tap any number of creatures you control with total power 4 or more: This Vehicle becomes an artifact creature until end of turn.)

Altar of Shadows

At the beginning of your first main phase, add {B} for each charge counter on this artifact.
{7}, {T}: Destroy target creature. Then put a charge counter on this artifact.

Bloodline Pretender

Changeling (This card is every creature type.)
As this creature enters, choose a creature type.
Whenever another creature you control of the chosen type enters, put a +1/+1 counter on this creature.

Bojuka Bog

This land enters tapped.
When this land enters, exile target player's graveyard.
{T}: Add {B}.

Field of Ruin

{T}: Add {C}.
{2}, {T}, Sacrifice this land: Destroy target nonbasic land an opponent controls. Each player searches their library for a basic land card, puts it onto the battlefield, then shuffles.

Evolving Wilds

Mortuary Mire

This land enters tapped.
When this land enters, you may put target creature card from your graveyard on top of your library.
{T}: Add {B}.

Temple of the False God

{T}: Add {C}{C}. Activate only if you control five or more lands.

Swamp

Guildless Commons

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

Barricade Breaker

Improvise (Your artifacts can help cast this spell. Each artifact you tap after you're done activating mana abilities pays for {1}.)
This creature attacks each combat if able.

Automated Artificer

{T}: Add {C}. Spend this mana only to activate an ability or cast an artifact spell.

Agent of the Iron Throne

Commander creatures you own have "Whenever an artifact or creature you control is put into a graveyard from the battlefield, each opponent loses 1 life."

Abandoned Sarcophagus

You may cast spells that have a cycling ability from your graveyard.
If a card that has a cycling ability would be put into your graveyard from anywhere and it wasn't cycled, exile it instead.

Bone Offering

Create a tapped 4/1 black Skeleton creature token with menace. (Then exile this card. You may cast the artifact later from exile.)

Altar of Bhaal

{2}{B}, {T}, Exile a creature you control: Return target creature card from your graveyard to the battlefield. Activate only as a sorcery.

Altar of Bhaal // Bone Offering

Bag of Devouring

Whenever you sacrifice another nontoken artifact or creature, exile it.
{2}, {T}, Sacrifice another artifact or creature: Draw a card.
{3}, {T}, Sacrifice this artifact: Roll a d10. Return up to X cards from among cards exiled with this artifact to their owners' hands, where X is the result.

Tectonic Edge

{T}: Add {C}.
{1}, {T}, Sacrifice this land: Destroy target nonbasic land. Activate only if an opponent controls four or more lands.

Myriad Landscape

This land enters tapped.
{T}: Add {C}.
{2}, {T}, Sacrifice this land: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

Witch's Cottage

({T}: Add {B}.)
This land enters tapped unless you control three or more other Swamps.
When this land enters untapped, you may put target creature card from your graveyard on top of your library.