Boreas Charger

Flying
When Boreas Charger leaves the battlefield, choose an opponent who controls more lands than you. Search your library for a number of Plains cards equal to the difference, reveal those cards, put one of them onto the battlefield tapped and the rest into your hand, then shuffle.

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.)

Hourglass of the Lost

{T}: Add {W}. Put a time counter on Hourglass of the Lost.
{T}, Remove X time counters from Hourglass of the Lost and exile it: Return each nonland permanent card with mana value X from your graveyard to the battlefield. Activate only as a sorcery.

Burnished Hart

{3}, Sacrifice this creature: Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Deep Gnome Terramancer

Flash
Mold Earth — Whenever one or more lands enter under an opponent's control without being played, you may search your library for a Plains card, put it onto the battlefield tapped, then shuffle. Do this only once each turn.

Knight of the White Orchid

First strike
When Knight of the White Orchid enters, if an opponent controls more lands than you, you may search your library for a Plains card, put it onto the battlefield, then shuffle.

Celestine, the Living Saint

Flying, lifelink
Healing Tears — At the beginning of your end step, return target creature card with mana value X or less from your graveyard to the battlefield, where X is the amount of life you gained this turn.

War Room

{T}: Add {C}.
{3}, {T}, Pay life equal to the number of colors in your commanders' color identity: Draw a card.

Tyrite Sanctum

{T}: Add {C}.
{2}, {T}: Target legendary creature becomes a God in addition to its other types. Put a +1/+1 counter on it.
{4}, {T}, Sacrifice Tyrite Sanctum: Put an indestructible counter on target God.

Monologue Tax

Whenever an opponent casts their second spell each turn, you create a Treasure token.

Plains

Tempting Contract

At the beginning of your upkeep, each opponent may create a Treasure token. For each opponent who does, you create a Treasure token.

Radiant Fountain

When Radiant Fountain enters, you gain 2 life.
{T}: Add {C}.

New Benalia

New Benalia enters tapped.
When New Benalia enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)
{T}: Add {W}.

Lotus Field

Hexproof
Lotus Field enters tapped.
When Lotus Field enters, sacrifice two lands.
{T}: Add three mana of any one color.

Kor Cartographer

When Kor Cartographer enters, you may search your library for a Plains card, put it onto the battlefield tapped, then shuffle.

Solemn Simulacrum

When this creature enters, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
When this creature dies, you may draw a card.

Karoo

Karoo enters tapped.
When Karoo enters, sacrifice it unless you return an untapped Plains you control to its owner's hand.
{T}: Add {C}{W}.

Sol Ring

Blighted Steppe

{T}: Add {C}.
{3}{W}, {T}, Sacrifice Blighted Steppe: You gain 2 life for each creature you control.