Rienne, Angel of Rebirth
Legendary Creature — Angel
Flying
Other multicolored creatures you control get +1/+0.
Whenever another multicolored creature you control dies, return it to its owner's hand at the beginning of the next end step.
Illustrated by
Dominaria United Commander#166MythicEnglishLegality
Rulings
If a multicolored creature you control leaves the graveyard after it dies but before the delayed triggered ability resolves, it will not return to its owner's hand.
If an effect causes a non-multicolored creature to become multicolored and that creature dies, the non-multicolored card will return to its owner's hand.
If Rienne dies at the same time as one or more other multicolored creatures you control, its last ability triggers for each of those creatures.
If Rienne leaves the battlefield after its ability has triggered but before the next end step, its delayed triggered ability will still return the card.