Sauron, the Necromancer — ruling 1

The token copies exactly what was printed on the original card and nothing else, except the characteristics it specifically modifies. It doesn't copy any information about the object the card was before it was put into your graveyard.

Sauron, the Necromancer — ruling 2

The token is a Wraith instead of its other creature types (and other subtypes if it has any) and is black instead of its other colors. Its base power and toughness are 3/3. These are copiable values of the token that other effects may copy.

Sauron, the Necromancer — ruling 3

If the card copied by the token had any "when [this permanent] enters the battlefield" abilities, then the token also has those abilities and will trigger them when it's created. Similarly, any "as [this permanent] enters the battlefield" or "[this permanent] enters the battlefield with" abilities that the token has copied will also work.

Sauron, the Necromancer — ruling 4

If the exiled card has {X} in its mana cost, X is 0.

Sauron, the Necromancer — ruling 5

The delayed triggered ability will exile the token at the beginning of your next end step unless Sauron, the Necromancer is your Ring-bearer at the time that the ability resolves. If Sauron, the Necromancer leaves the battlefield before the delayed triggered ability resolves, that ability will exile the token, even if Sauron, the Necromancer later returns to the battlefield or you control another copy of Sauron, the Necromancer as your Ring-bearer.

Sauron, the Necromancer : règles, fonctionnement et interactions (MTG)

Sauron, the Necromancer 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

Menace Whenever Sauron attacks, exile target creature card from your graveyard. Create a tapped and attacking token that's a copy of that card, except it's a 3/3 black Wraith with menace. At the beginning of the next end step, exile that token unless Sauron is your Ring-bearer.

How it works : Sauron, the Necromancer

Original English text — Wizards of the Coast / Scryfall

#1June 16, 2023· Wizards of the Coast
The token copies exactly what was printed on the original card and nothing else, except the characteristics it specifically modifies. It doesn't copy any information about the object the card was before it was put into your graveyard.
Card named in this ruling
Copy
#2June 16, 2023· Wizards of the Coast
The token is a Wraith instead of its other creature types (and other subtypes if it has any) and is black instead of its other colors. Its base power and toughness are 3/3. These are copiable values of the token that other effects may copy.
Card named in this ruling
Copy
#3June 16, 2023· Wizards of the Coast
If the card copied by the token had any "when [this permanent] enters the battlefield" abilities, then the token also has those abilities and will trigger them when it's created. Similarly, any "as [this permanent] enters the battlefield" or "[this permanent] enters the battlefield with" abilities that the token has copied will also work.
No other card is named in this ruling.
#4June 16, 2023· Wizards of the Coast
If the exiled card has in its mana cost, X is 0.
No other card is named in this ruling.
#5June 16, 2023· Wizards of the Coast
The delayed triggered ability will exile the token at the beginning of your next end step unless Sauron, the Necromancer is your Ring-bearer at the time that the ability resolves. If Sauron, the Necromancer leaves the battlefield before the delayed triggered ability resolves, that ability will exile the token, even if Sauron, the Necromancer later returns to the battlefield or you control another copy of Sauron, the Necromancer as your Ring-bearer.
Card named in this ruling
Copy