4 Colors

Four players, one deck, and a race to empty your hand first - that's the whole setup in 4 Colors. You're up against three computer opponents, matching cards by color or number and hoping they don't drop an action card right when you're about to win.

Here's the catch that trips everyone up eventually: forget to shout "Uno" when you're down to one card, and you're stuck drawing two more. It's a small rule that turns a relaxed match into a genuinely tense one.

Action cards are where the chaos lives. They can flip your strategy upside down mid-turn, so every match plays out a little differently depending on when they show up. If matching and thinking ahead is your kind of fun, this sits nicely alongside other Cards games and the site's Brain Training Games.

It runs free in the browser on Android, iOS, and desktop, no download needed. Good for a quick round or three in a row.

Get rid of all your cards before your three computer opponents do. Click or tap a card that matches the current color or number to play it. No match in hand? Draw from the deck and try again on your next turn.

Watch for action cards - they can shake up the board fast and change your plan on the spot. And don't forget to signal when you're down to your last card, or you'll be drawing two extra as a penalty. Every move matters, so think before you tap.