Archon of Coronation

Flying
When Archon of Coronation enters, you become the monarch.
As long as you're the monarch, damage doesn't cause you to lose life. (When a creature deals combat damage to you, its controller still becomes the monarch.)

Ajani's Welcome

Whenever a creature you control enters, you gain 1 life.

Anafenza, Kin-Tree Spirit

Whenever another nontoken creature you control enters, bolster 1. (Choose a creature with the least toughness among creatures you control and put a +1/+1 counter on it.)

Angelheart Protector

When Angelheart Protector enters, target creature you control gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)