Overview
Two to six players, 168 cards, and a deck built to punish you. UNO Show 'em No Mercy is the 2023 edition, and the interesting thing about it is not the new cards — it is that Mattel took the house rules everybody already played and printed them as official.
Stacking, the seven-swap, the zero-pass, drawing until you can play, and Reverse acting as a Skip with two players are all in this sheet in black and white. Every one of them is absent from the classic UNO sheet. If you have ever lost an argument about stacking, this is the game where you were right.
Written against Mattel's instruction sheet for item HWV18 (PDF, ©2023), quoted where the wording matters.
1. The deck
The sheet states the total and nothing else:
Contents 168 Cards
There is no itemised breakdown — unusual for an UNO sheet, and worth knowing before you trust a card-by-card list you find elsewhere. What the sheet does name, in the action-card and scoring sections, is which cards exist:
Coloured action cards — Skip, Reverse, Draw 2, Draw 4, Discard All, Skip Everyone.
Wild action cards — Wild Reverse Draw 4, Wild Draw 6, Wild Draw 10, Wild Color Roulette.
Note that Draw Four exists as an ordinary coloured card here, separate from the wilds. That is new, and it is what makes the stacking ladder work.
2. Setup
- Choose a dealer and shuffle. The sheet offers a practical note — 168 cards is a lot, so split the deck between players if you cannot shuffle it.
- Deal seven cards each.
- The rest form the draw pile, face down.
- Turn the top card face up to start the discard pile. If it is an action card, ignore it and flip the next one — no opening-card special cases.
- Left of the dealer goes first, clockwise.
3. A turn
You must match colour, number or symbol. If you can, you may play. If you cannot:
If you DO NOT HAVE a matching card, you MUST draw cards from the Draw Pile UNTIL YOU DRAW A CARD YOU CAN PLAY. Then, play that card.
Two things follow that surprise people coming from classic UNO. You draw until playable, not one card. And you must then play it — there is no option to hold it, and no option to decline a playable card. Classic UNO allows both.
4. Stacking — official, with a ladder
This is the headline rule, and it is printed:
Stacking — If someone plays a Draw Card (+2, +4, +6, +10) you can "Stack" the penalty by playing a Draw Card from your hand of equal or higher value. If you do, the card you played adds to the total penalty for the next player.
The sheet's own example: someone plays +4 on you, you answer with +6, and the next player faces 10 cards — unless they can play a +6 or higher, in which case it passes on again.
This continues until someone can't play a Draw Card that equals or exceeds the value of the last card played. That player then takes the full penalty of all stacked Draw Cards.
The constraint is equal or higher, by value. You cannot answer a +6 with a +2. That single clause is what stops the chain being infinite, and it is the part people most often get wrong when carrying the rule over from house play.
5. Mercy — the knockout
Mercy — If a player ever has 25 or more cards in their hand, they are out of the game.
Their hand is set aside until the deck needs reshuffling. This is the second way to win: outlast everyone rather than empty your hand.
Note the trigger is 25 or more, checked at any moment — a stacked +10 landing on a player holding 16 ends them on the spot.
6. Zeros and sevens
Both of the famous house rules, printed:
0's Pass — When you play a 0 card of any color, ALL players must pass their hand to the next player in the current direction of play.
7's Swap — When you play a 7 card of any color, you MUST swap your hand with another player of your choice.
"MUST" is the sheet's own emphasis on the seven. You do not get to decline it, and you choose the victim. Play then continues in the current order.
7. The coloured action cards
| Card | Effect |
|---|---|
| Draw Two | Next player draws 2 and loses their turn |
| Draw Four | Next player draws 4 and loses their turn |
| Skip | Next player loses their turn |
| Reverse | Direction reverses |
| Discard All | Discard every card in your hand matching the Discard All card's colour, placed under it |
| Skip Everyone | Skip all other players and take another turn |
Reverse with two players is settled here, unlike in classic UNO:
With just two players a Reverse skips the other player, letting you take another turn.
8. The wild action cards
Wild Draw 6 — next player draws 6 and loses their turn.
Wild Draw 10 — next player draws 10 and loses their turn.
Wild Reverse Draw 4 — reverse the direction, then the next player in the new direction draws 4 and loses their turn. With two players the sheet spells out the trap:
With just two players this card skips the other player and makes YOU draw 4 cards! You may use the stacking rule to send the penalty back to the other player.
Wild Color Roulette — the next player names a colour, then reveals cards one at a time from the draw pile until one of that colour appears. Wilds do not count. They take every revealed card and lose their turn. The player being punished picks the colour, which is the joke: you are betting against your own luck.
9. Calling UNO
One card in hand, shout it. If someone catches you before the next player begins their turn, you draw two. Same as classic.
10. Winning, and the optional score
You win by emptying your hand, or by being the last player not knocked out.
Scoring is explicitly optional. If you use it:
| Cards left in opponents' hands | Value |
|---|---|
| Number cards 0–9 | Face value |
| Any coloured action card | 20 |
| Any wild action card | 50 |
| Bonus: each player knocked out during the hand | 250 |
A knocked-out player's remaining cards are ignored — you take the flat 250. First to 1,000 points wins.
11. What the sheet does not say
- The plain Wild card is never described. The deck contains them, but the sheet's action-card section covers only the four wild action cards, and the scoring table lists only those four. There is no printed instruction that a Wild lets you choose the colour. In practice everyone plays it as a classic Wild.
- There is no Wild Draw Four challenge. Classic UNO's "you may only play this if you hold no matching colour" condition, and the challenge that enforces it, are both absent. Draw cards here appear to be playable whenever they match.
- No itemised card list, so the composition of the 168 is not verifiable from the sheet.
- Nothing about whether Discard All's extra cards trigger anything — they go under the card and that is all it says.
Commonly argued
- Stacking is official here. Equal or higher value only. A +2 cannot answer a +6.
- It is not official in classic UNO. Different game, different sheet.
- Mercy triggers at 25 or more cards, at any moment, not at end of turn.
- You draw until you can play, then you must play it. No holding, no declining.
- Sevens force a swap and you choose who with. Zeros pass everything along.
- Reverse is a Skip with two players, stated in the sheet.
- Wild Reverse Draw 4 hits you in a two-player game unless you stack out of it.
- A knockout is worth a flat 250 and their hand is ignored.
Where this comes from
Mattel's instruction sheet for UNO Show 'em No Mercy, item HWV18, ©2023, four languages, hosted on Mattel's own servers. Same caveats as every sheet of this kind: it is one printing of one SKU, Mattel does not version these documents, and it is short enough to leave real gaps — the plain Wild card being the obvious one.
Where this entry and the sheet disagree, the sheet wins. Tell us.
Spotted a mistake?
Corrections are reviewed by an editor before they publish.