msem-instigator

Whenever another creature you control enters, Flightpath Trainee gains flying until end of turn.

Populate, then you gain 2 life. (Create a token that's a copy of a creature token you control.)

Flying, lifelink

Vigilance
{W}: Heaven's Champion gains first strike until end of turn.

Flying (This creature can't be blocked except by creatures with flying or reach.)
Heavensent Emissary enters with a +1/+1 counter on it for each other creature with flying you control.

Creatures you control get +1/+1 until end of turn. Token creatures you control get an additional +1/+1 until end of turn.

Create a 2/2 white Knight creature token with vigilance, then populate. (Create a token that's a copy of a creature token you control.)

Enchant creature
When Knightly Valor enters, create a 2/2 white Knight creature token with vigilance. (Attacking doesn't cause it to tap.)
Enchanted creature gets +2/+2 and has vigilance.

When Knight's Attendant enters, create a 2/2 white Knight creature token with vigilance.

Prevent all damage that would be dealt to you this turn. You gain 1 life for each creature you control.

Whenever you gain life, you may pay {X}, where X is less than or equal to the amount of life you gained. If you do, draw X cards.

When Mass Orator enters, if it isn't a token, populate. (Create a token that's a copy of a creature token you control.)
Creature tokens you control get +1/+1.

Flying
Whenever another creature you control attacks, you may pay {1}. If you do, put a +1/+1 counter on it.

[+1]: You gain 1 life. Put a +1/+1 counter on up to one target creature.
[–3]: Exile target creature. Its controller gains life equal to its power.
[–8]: You get an emblem with “Creatures you control get +1/+1 and have double strike and lifelink.”

When Seluriel's Blessing enters, put a +1/+1 counter on each creature you control.
Creatures you control enter with an additional +1/+1 counter on them.
Creatures you control with counters on them have vigilance and indestructible.

Whenever another creature enters, you gain 1 life.

Instant and sorcery spells your opponents cast cost {1} more to cast.

Whenever a creature you control enters, if you didn't cast it from your hand, put a +1/+1 counter on it.
{3}{W}: Exile target creature you control, then return it to the battlefield under its owner's control.

Until end of turn, target creature gets +1/+1 and gains lifelink.

Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Flying (This creature can't be blocked except by creatures with flying or reach.)
When Trained Warhawk enters, create a 1/1 white Soldier creature token.

{4}{W}{W}: Create a 4/4 white Angel creature token with flying.
{2}{W}{W}: Populate. (Create a token that's a copy of a creature token you control.)

Defender (This creature can't attack.)
Whenever Wall of Hope is dealt damage, you gain that much life.

Destroy target enchantment, then create a 1/1 white Soldier creature token.