UNO Mattel Official UNO Birthday Gift Flip Double-Sided Multiplayer Party Board Game GDR44

Wild +2 card can be played only if the player has no card matching the discard pile color; next player draws two cards and skips turn

Players must call "UNO" when playing their second to last card or draw two penalty cards if caught not calling

Total of 76 number cards (1-9 in four colors, two copies each per side) and 32 functional cards per side

Enhanced strategic gameplay by revealing opponents’ card backs on the "Dark" side

Both versions feature innovative double-sided cards and the Flip mechanic that changes gameplay dynamics between Light and Dark sides, offering a fresh and challenging twist on classic UNO.