Yes, in Uno, if you have no other playable cards, you must draw 4 cards from the deck.
No, in Uno, you cannot stack draw 4 cards.
These cards are from Uno.
If you don't say "uno," you draw two cards.
If you forget to say "uno," you draw two cards.
If you forget to say "uno," you must draw two cards.
If you forget to call "uno," you must draw two cards.
No, you cannot draw 99 Uno cards in one turn.
If someone says "Uno" before you in a game of Uno, you must draw two cards.
In Uno, the challenge system allows a player to challenge another player if they suspect that the player who just played a card could have played a different card instead. If the challenged player is found to have a playable card in their hand, they must draw four cards as a penalty. If the challenged player did not have a playable card, the challenger must draw six cards instead.
If you forget to say "uno" in the card game, you have to draw two cards.
If someone says "uno" before you, you draw two cards.
In Uno, you can stack Draw 2 and Draw 4 cards on top of each other. If a player receives multiple Draw 2 or Draw 4 cards in a row, they can stack them and the next player must draw the total number of cards indicated.