+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.”
A player who has a card in hand can't choose to lose 3 life instead of discarding a card.
23-06-2020
wotc
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.
23-06-2020
wotc
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.
23-06-2020
wotc
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.
23-06-2020
wotc
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.
23-06-2020
wotc
Creatures put onto the battlefield with Liliana's emblem gain haste indefinitely.
Random a card of Magic: The Gathering (MTG), but you can also roll the D20 dice, random a Planeswalker, have fun with the random rules and more.