Enchant creature
Enchanted creature gets +2/+2, has first strike, and is a Knight in addition to its other types. (It deals combat damage before creatures without first strike.)

Ledev Guardian

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)

Conclave Tribunal

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
When this enchantment enters, exile target nonland permanent an opponent controls until this enchantment leaves the battlefield.

Worthy Knight

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

Raise the Alarm

Create two 1/1 white Soldier creature tokens.

Luminous Bonds

Enchant creature
Enchanted creature can't attack or block.

Plains

Novice Knight

Defender (This creature can't attack.)
As long as this creature is enchanted or equipped, it can attack as though it didn't have defender.

Shining Armor

Flash
When this Equipment enters, attach it to target Knight you control.
Equipped creature gets +0/+2 and has vigilance.
Equip {3} ({3}: Attach to target creature you control. Equip only as a sorcery.)

Cavalry Drillmaster

When this creature enters, target creature gets +2/+0 and gains first strike until end of turn. (It deals combat damage before creatures without first strike.)

Thriving Heath

This land enters tapped. As it enters, choose a color other than white.
{T}: Add {W} or one mana of the chosen color.

Inspiring Captain

When this creature enters, creatures you control get +1/+1 until end of turn.

Gallant Cavalry

Vigilance (Attacking doesn't cause this creature to tap.)
When this creature enters, create a 2/2 white Knight creature token with vigilance.

Danitha Capashen, Paragon

First strike, vigilance, lifelink
Aura and Equipment spells you cast cost {1} less to cast.

Dizzying Swoop

Tap up to two target creatures. (Then exile this card. You may cast the creature later from exile.)