Flooded Strand

{T}, Pay 1 life, Sacrifice Flooded Strand: Search your library for a Plains or Island card, put it onto the battlefield, then shuffle.

Floodfarm Verge

{T}: Add {W}.
{T}: Add {U}. Activate only if you control a Plains or an Island.

Sting, the Glinting Dagger

Equipped creature gets +1/+1 and has haste.
At the beginning of each combat, untap equipped creature.
Equipped creature has first strike as long as it's blocking or blocked by a Goblin or Orc.
Equip {2}

Intellectual Offering

Choose an opponent. You and that player each draw three cards.
Choose an opponent. Untap all nonland permanents you control and all nonland permanents that player controls.

Island

Spectator Seating

Spectator Seating enters tapped unless you have two or more opponents.
{T}: Add {R} or {W}.

Sea of Clouds

Sea of Clouds enters tapped unless you have two or more opponents.
{T}: Add {W} or {U}.

Boros Garrison

Boros Garrison enters tapped.
When Boros Garrison enters, return a land you control to its owner's hand.
{T}: Add {R}{W}.

Arid Mesa

{T}, Pay 1 life, Sacrifice Arid Mesa: Search your library for a Mountain or Plains card, put it onto the battlefield, then shuffle.

Sundown Pass

Sundown Pass enters tapped unless you control two or more other lands.
{T}: Add {R} or {W}.

Neko-Te

Whenever equipped creature deals damage to a creature, tap that creature. That creature doesn't untap during its controller's untap step for as long as Neko-Te remains on the battlefield.
Whenever equipped creature deals damage to a player, that player loses 1 life.
Equip {2}

Plains

Steam Vents

({T}: Add {U} or {R}.)
As Steam Vents enters, you may pay 2 life. If you don't, it enters tapped.

Training Center

Training Center enters tapped unless you have two or more opponents.
{T}: Add {U} or {R}.

Command Tower

{T}: Add one mana of any color in your commander's color identity.

Gold Myr

Yasmin Khan

{T}: Exile the top card of your library. Until your next end step, you may play it.
Doctor's companion (You can have two commanders if the other is the Doctor.)

Grim Reaper's Sprint

Morbid — This spell costs {3} less to cast if a creature died this turn.
Enchant creature
When Grim Reaper's Sprint enters, untap each creature you control. If it's your main phase, there is an additional combat phase after this phase.
Enchanted creature gets +2/+2 and has haste.

Stormcarved Coast

Stormcarved Coast enters tapped unless you control two or more other lands.
{T}: Add {U} or {R}.

Mystic Monastery

Mystic Monastery enters tapped.
{T}: Add {U}, {R}, or {W}.

Scalding Tarn

{T}, Pay 1 life, Sacrifice Scalding Tarn: Search your library for an Island or Mountain card, put it onto the battlefield, then shuffle.

Gorgon Flail

Equipped creature gets +1/+1 and has deathtouch. (Any amount of damage it deals to a creature is enough to destroy that creature.)
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Mountain

Prop Room

Untap each creature you control during each other player's untap step.
(You may cast either half. That door unlocks on the battlefield. As a sorcery, you may pay the mana cost of a locked door to unlock it.)

Dazzling Theater

Creature spells you cast have convoke. (Your creatures can help cast those spells. Each creature you tap while casting a creature spell pays for {1} or one mana of that creature's color.)
(You may cast either half. That door unlocks on the battlefield. As a sorcery, you may pay the mana cost of a locked door to unlock it.)

Dazzling Theater // Prop Room

Thundering Falls

({T}: Add {U} or {R}.)
Thundering Falls enters tapped.
When Thundering Falls enters, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

The Fifth Doctor

Peaceful Coexistence — At the beginning of your end step, put a +1/+1 counter on each creature you control that didn't attack or enter this turn. Untap those creatures.

Hallowed Fountain

({T}: Add {W} or {U}.)
As Hallowed Fountain enters, you may pay 2 life. If you don't, it enters tapped.

Lulu, Loyal Hollyphant

Flying
At the beginning of your end step, if a permanent you controlled left the battlefield this turn, put a +1/+1 counter on each tapped creature you control, then untap them.
Choose a Background (You can have a Background as a second commander.)

Ardenvale Fealty

Create a 2/2 white Knight creature token with vigilance. (Then exile this card. You may cast the enchantment later from exile.)

Virtue of Loyalty

At the beginning of your end step, put a +1/+1 counter on each creature you control. Untap those creatures.

Virtue of Loyalty // Ardenvale Fealty

Arm with Aether

Until end of turn, creatures you control gain "Whenever this creature deals damage to an opponent, you may return target creature that player controls to its owner's hand."

Iron Myr

Polymorphist's Jest

Until end of turn, each creature target player controls loses all abilities and becomes a blue Frog with base power and toughness 1/1.

Izzet Boilerworks

Izzet Boilerworks enters tapped.
When Izzet Boilerworks enters, return a land you control to its owner's hand.
{T}: Add {U}{R}.

Staff of Nin

At the beginning of your upkeep, draw a card.
{T}: Staff of Nin deals 1 damage to any target.

Azorius Chancery

Azorius Chancery enters tapped.
When Azorius Chancery enters, return a land you control to its owner's hand.
{T}: Add {W}{U}.

Silver Myr

Drumbellower

Flying
Untap all creatures you control during each other player's untap step.

Sacred Foundry

({T}: Add {R} or {W}.)
As Sacred Foundry enters, you may pay 2 life. If you don't, it enters tapped.

Deserted Beach

Deserted Beach enters tapped unless you control two or more other lands.
{T}: Add {W} or {U}.

Sol Ring

Exotic Orchard

{T}: Add one mana of any color that a land an opponent controls could produce.

Path of Ancestry

Path of Ancestry enters tapped.
{T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Halo Fountain

{W}, {T}, Untap a tapped creature you control: Create a 1/1 green and white Citizen creature token.
{W}{W}, {T}, Untap two tapped creatures you control: Draw a card.
{W}{W}{W}{W}{W}, {T}, Untap fifteen tapped creatures you control: You win the game.

Energy Arc

Untap any number of target creatures. Prevent all combat damage that would be dealt to and dealt by those creatures this turn.

Raugrin Triome

({T}: Add {U}, {R}, or {W}.)
Raugrin Triome enters tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Elegant Parlor

({T}: Add {R} or {W}.)
Elegant Parlor enters tapped.
When Elegant Parlor enters, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Mass Diminish

Until your next turn, creatures target player controls have base power and toughness 1/1.
Flashback {3}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Reflecting Pool

{T}: Add one mana of any type that a land you control could produce.

Meticulous Archive

({T}: Add {W} or {U}.)
Meticulous Archive enters tapped.
When Meticulous Archive enters, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)