Argivian Cavalier

Enlist (As this creature attacks, you may tap a nonattacking creature you control without summoning sickness. When you do, add its power to this creature's until end of turn.)
When this creature enters, create a 1/1 white Soldier creature token.

Join Forces

Untap up to two target creatures. They each get +2/+2 until end of turn.

Crystal Grotto

When this land enters, scry 1.
{T}: Add {C}.
{1}, {T}: Add one mana of any color.

Samite Herbalist

Whenever this creature becomes tapped, you gain 1 life and scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Love Song of Night and Day

Read ahead (Choose a chapter and start with that many lore counters. Add one after your draw step. Skipped chapters don't trigger. Sacrifice after III.)
I — You and target opponent each draw two cards.
II — Create a 1/1 white Bird creature token with flying.
III — Put a +1/+1 counter on each of up to two target creatures.

Plains

Serra Redeemer

Flying
Whenever another creature you control with power 2 or less enters, put two +1/+1 counters on that creature.

Guardian of New Benalia

Enlist (As this creature attacks, you may tap a nonattacking creature you control without summoning sickness. When you do, add its power to this creature's until end of turn.)
Whenever this creature enlists a creature, scry 2.
Discard a card: This creature gains indestructible until end of turn. Tap it.

Charismatic Vanguard

{4}{W}: Creatures you control get +1/+1 until end of turn.

Take Up the Shield

Put a +1/+1 counter on target creature. It gains lifelink and indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

Prayer of Binding

Flash
When this enchantment enters, exile up to one target nonland permanent an opponent controls until this enchantment leaves the battlefield. You gain 2 life.

Griffin Protector

Flying
Whenever another creature you control enters, this creature gets +1/+1 until end of turn.

Resolute Reinforcements

Flash (You may cast this spell any time you could cast an instant.)
When this creature enters, create a 1/1 white Soldier creature token.

Argivian Phalanx

Affinity for creatures (This spell costs {1} less to cast for each creature you control.)
Vigilance (Attacking doesn't cause this creature to tap.)