Liliana, Waker of the Dead — ruling 1

As Liliana's first ability resolves, first the player whose turn it is chooses a card in hand without revealing it, then each other player in turn order does the same. Then all the chosen cards are discarded at the same time. Finally, each opponent who couldn't discard a card loses 3 life.

Liliana, Waker of the Dead — ruling 2

A player who has a card in hand can't choose to lose 3 life instead of discarding a card.

Liliana, Waker of the Dead — ruling 3

If you have no cards in hand, you just don't discard anything. You don't lose 3 life. Other players still discard if able.

Liliana, Waker of the Dead — ruling 4

The value of X is determined only as Liliana's second ability resolves. Once that happens, the value of X won't change later in the turn even if the number of cards in your graveyard changes.

Liliana, Waker of the Dead — ruling 5

Creatures put onto the battlefield with Liliana's emblem gain haste indefinitely.

Liliana, Waker of the Dead — ruling 6

In a multiplayer game, if a player leaves the game, all cards that player owns leave as well. If you leave the game, any permanents you control from Liliana's emblem are exiled.

Liliana, Waker of the Dead : règles, fonctionnement et interactions (MTG)

Liliana, Waker of the Dead 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

+1: Each player discards a card. Each opponent who can't loses 3 life. −3: Target creature gets -X/-X until end of turn, where X is the number of cards in your graveyard. −7: You get an emblem with "At the beginning of combat on your turn, put target creature card from a graveyard onto the battlefield under your control. It gains haste."

How it works : Liliana, Waker of the Dead

Original English text — Wizards of the Coast / Scryfall

#1June 23, 2020· Wizards of the Coast
As Liliana's first ability resolves, first the player whose turn it is chooses a card in hand without revealing it, then each other player in turn order does the same. Then all the chosen cards are discarded at the same time. Finally, each opponent who couldn't discard a card loses 3 life.
No other card is named in this ruling.
#2June 23, 2020· Wizards of the Coast
A player who has a card in hand can't choose to lose 3 life instead of discarding a card.
No other card is named in this ruling.
#3June 23, 2020· Wizards of the Coast
If you have no cards in hand, you just don't discard anything. You don't lose 3 life. Other players still discard if able.
No other card is named in this ruling.
#4June 23, 2020· Wizards of the Coast
The value of X is determined only as Liliana's second ability resolves. Once that happens, the value of X won't change later in the turn even if the number of cards in your graveyard changes.
No other card is named in this ruling.
#5June 23, 2020· Wizards of the Coast
Creatures put onto the battlefield with Liliana's emblem gain haste indefinitely.
No other card is named in this ruling.
#6June 23, 2020· Wizards of the Coast
In a multiplayer game, if a player leaves the game, all cards that player owns leave as well. If you leave the game, any permanents you control from Liliana's emblem are exiled.
No other card is named in this ruling.