Encase Soul

Create a legendery black token Enchantment
Artifact named Empty Soul and a black token
Enchantment Artifact named Soul Egg.
Empty Soul has "When this artifact enters
the battlefield, equip it to target creature you control
with mana value 3 or less.Equipped Creature has
Shroud and Indestructible."
Soul Egg has "Equip 3. While Soul Egg is equipped,
Empty Soul has hexproof and indestructible."