Razia, Boros Archangel — ruling 1

The 3 damage doesn’t have to be from the same source, and it doesn’t have to be all dealt at once. If only 2 damage is redirected, the next 1 damage will also be redirected.

Razia, Boros Archangel — ruling 2

If either target creature leaves the battlefield before damage is dealt, that damage won’t be redirected. It doesn’t matter if Razia leaves the battlefield.

Razia, Boros Archangel : règles, fonctionnement et interactions (MTG)

Razia, Boros Archangel is one of those cards players keep asking about. Here is, in plain words, what its official text says, the rulings published by Wizards of the Coast, and the combos players actually run.

Official card text

Flying, vigilance, haste : The next 3 damage that would be dealt to target creature you control this turn is dealt to another target creature instead.

How it works : Razia, Boros Archangel

Original English text — Wizards of the Coast / Scryfall

#1October 1, 2005· Wizards of the Coast
The 3 damage doesn’t have to be from the same source, and it doesn’t have to be all dealt at once. If only 2 damage is redirected, the next 1 damage will also be redirected.
No other card is named in this ruling.
#2October 1, 2005· Wizards of the Coast
If either target creature leaves the battlefield before damage is dealt, that damage won’t be redirected. It doesn’t matter if Razia leaves the battlefield.
No other card is named in this ruling.