Fateful Absence

Destroy target creature or planeswalker. Its controller investigates. (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")

Werefox Bodyguard

Flash
When this creature enters, exile up to one other target non-Fox creature until this creature leaves the battlefield.
{1}{W}, Sacrifice this creature: You gain 2 life.

Battlefield Forge

{T}: Add {C}.
{T}: Add {R} or {W}. This land deals 1 damage to you.

Inspiring Veteran

Marshal of Zhalfir

Other Knights you control get +1/+1.
{W}{U}, {T}: Tap another target creature.

Unclaimed Territory

As this land enters, choose a creature type.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type.

Basri's Lieutenant

Vigilance, protection from multicolored
When this creature enters, put a +1/+1 counter on target creature you control.
Whenever this creature or another creature you control dies, if it had a +1/+1 counter on it, create a 2/2 white Knight creature token with vigilance.

Tournament Grounds

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

Benalish Marshal

Sunrise Cavalier

Trample, haste
If it's neither day nor night, it becomes day as this creature enters.
Whenever day becomes night or night becomes day, put a +1/+1 counter on target creature you control.

Venerable Knight

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

Prairie Stream

({T}: Add {W} or {U}.)
This land enters tapped unless you control two or more basic lands.

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.

Dauntless Bodyguard

As this creature enters, choose another creature you control.
Sacrifice this creature: The chosen creature gains indestructible until end of turn.

Belenon War Anthem

Invasion of Belenon

(As a Siege enters, choose an opponent to protect it. You and others can attack it. When it's defeated, exile it, then cast it transformed.)
When this Siege enters, create a 2/2 white and blue Knight creature token with vigilance.

Invasion of Belenon // Belenon War Anthem

Plains

Secluded Courtyard

As this land enters, choose a creature type.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type or activate an ability of a creature source of the chosen type.

The Circle of Loyalty

Affinity for Knights (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.

Teferi Akosa of Zhalfir

+1: Draw two cards. Then discard two cards unless you discard a creature card.
−2: You get an emblem with "Knights you control get +1/+0 and have ward {1}."
−3: Tap any number of untapped creatures you control. When you do, shuffle target nonland permanent an opponent controls with mana value X or less into its owner's library, where X is the number of creatures tapped this way.

Invasion of New Phyrexia

(As a Siege enters, choose an opponent to protect it. You and others can attack it. When it's defeated, exile it, then cast it transformed.)
When this Siege enters, create X 2/2 white and blue Knight creature tokens with vigilance.

Invasion of New Phyrexia // Teferi Akosa of Zhalfir

Valiant Knight

Other Knights you control get +1/+1.
{3}{W}{W}: Knights you control gain double strike until end of turn.