UNO uses a dedicated colour deck. Its matching idea is related to Crazy Eights and Mau-Mau, but their special-card rules do not transfer. This guide covers classic base play using identified Mattel instructions. A particular edition’s extra cards need that edition’s own explanation.
In this guide
Core of the 108-card instructions
Mattel W2085: deal seven; match colour, number or symbol. Otherwise draw one, optionally playing only that card immediately. Skip skips, Reverse reverses, Draw Two draws two and skips. Wild chooses colour; Draw Four requires no held card of the active colour. A successful challenge makes its player draw four; a failed challenger draws six. Resolve pending draw penalties rather than stacking your own Draw Two/Four.
Further reading: Mattel: UNO instruction sheet W2085, 108-card edition
Check three attributes separately
On a red 6, blue 6 matches number, while red 3 matches colour. Blue 3 matches neither. An ordinary Wild supplies another route; Wild Draw Four additionally requires checking the rest of the hand. A matching number in another colour is different from holding the active colour.
Position as text
Top: red 6. Hand from left: red 3, blue 6, blue 3, Wild. Legal: 1, 2, 4.
Why red 3 and blue 6 differ
Our example hand on red 6 is red 3, blue 6 and Draw Four. Red 3 blocks legal Draw Four use. Remove it from the example: blue 6 still matches number, but there is no red hand card. The Draw Four colour test then changes. A challenge examines the hand as it was before that Draw Four was played.
Position as text
A: red 3, blue 6, Draw Four. B: green 3, blue 6, Draw Four. Blue 6 matches number in both, but is not a red card.
Calling, ending and remaining cards
GDJ85 calls for UNO at one remaining card; a missed call caught in time costs two cards. A final Draw Two/Four still makes the next player draw. Remaining values are printed numbers, 20 for Skip/Reverse/Draw Two and 50 for ordinary Wild/Draw Four. The round winner collects remaining-hand points toward 500. These values concern the stated base cards.
Further reading: Mattel: UNO instruction sheet GDJ85 (2018)