Plains

Concealed Courtyard

Concealed Courtyard enters tapped unless you control two or fewer other lands.
{T}: Add {W} or {B}.

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.

Blacklance Paragon

Flash
When Blacklance Paragon enters, target Knight gains deathtouch and lifelink until end of turn.

Knight of Malice

First strike (This creature deals combat damage before creatures without first strike.)
Hexproof from white (This creature can't be the target of white spells or abilities your opponents control.)
This creature gets +1/+0 as long as any player controls a white permanent.

Tournament Grounds

{T}: Add {C}.
{T}: Add {R}, {W}, or {B}. Spend this mana only to cast a Knight or Equipment spell.

Swamp

Isolated Chapel

Isolated Chapel enters tapped unless you control a Plains or a Swamp.
{T}: Add {W} or {B}.

History of Benalia

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I, II — Create a 2/2 white Knight creature token with vigilance.
III — Knights you control get +2/+1 until end of turn.

Venerable Knight

When Venerable Knight dies, put a +1/+1 counter on target Knight you control.

Benalish Marshal

Worthy Knight

Whenever you cast a Knight spell, create a 1/1 white Human creature token.

Knight of Grace

First strike (This creature deals combat damage before creatures without first strike.)
Hexproof from black (This creature can't be the target of black spells or abilities your opponents control.)
This creature gets +1/+0 as long as any player controls a black permanent.

The Circle of Loyalty

This spell costs {1} less to cast for each Knight you control.
Creatures you control get +1/+1.
Whenever you cast a legendary spell, create a 2/2 white Knight creature token with vigilance.
{3}{W}, {T}: Create a 2/2 white Knight creature token with vigilance.

Caves of Koilos

{T}: Add {C}.
{T}: Add {W} or {B}. Caves of Koilos deals 1 damage to you.

Knight of the Ebon Legion

{2}{B}: Knight of the Ebon Legion gets +3/+3 and gains deathtouch until end of turn.
At the beginning of your end step, if a player lost 4 or more life this turn, put a +1/+1 counter on Knight of the Ebon Legion. (Damage causes loss of life.)