Serra Avatar [Junior Super Series]Set: Junior Super Series Type: Creature Avatar Rarity: Rare Cost: {4}{W}{W}{W} Serra Avatar's power and toughness are each equal to your life total. When Serra Avatar is put into a graveyard from anywhere, shuffle it into its owner's library.

Nylea isn't a creature

you may search your library for an Ally creature card

Planeswalker (3)

which kithkin to trick

Set: EX: Crystal Guardians Type: Lightning Rarity: Uncommon Retreat cost: Colorless

you may put an Angel

Set: Portal Three Kingdoms Type: Legendary Creature — Human Soldier Rarity: Rare Cost: {4}{R} When Dong Zhou

Set: McDonald's Promos: 2018 Collection Type: Colorless Rarity: Promo Retreat cost: Colorless

Soratami Ascendant

Set: Amonkhet Prerelease Promos Type: Instant Rarity: Mythic Cost: {2}{R} End the turn

Set: Sword & Shield: Darkness Ablaze Type: Colorless Rarity: Secret Rare Retreat cost: Colorless

then puts it onto the battlefield if it's a permanent card