Hi-Lo Rocket

What is Hi-Lo Rocket?

Higher or lower (also called Hi-Lo) is about as simple as card games get. One card is face up. You guess whether the next card off the deck will be higher or lower. That's it. People have played it with a single deck at a kitchen table for generations, usually with a push-your-luck twist: keep going and win more, or stop while you're ahead.

Our version turns each streak of good guesses into a rocket flight. The higher you fly in one go, the more meters you can bank. Crash, and the whole flight is gone. It's free, plays in the browser on a phone, tablet or computer, and there's no download.

How to play

1. A card from a shuffled 52-card deck is turned face up.
2. Choose Higher or Lower. Each button shows how many meters a right call is worth and the chance it comes true.
3. If you're right, your rocket climbs and the new card becomes the one to beat.
4. If you're wrong, the rocket crashes and you lose every meter of that flight.
5. Hit Bank any time you have meters in the air. They're added to your score for good, and a new flight starts from the ground.
6. The run ends when the deck runs out. Anything still in the air at that point is banked automatically.

Your final score is the total meters you banked across the whole deck.

The key rules

• Ace is low and King is high. So the order runs A, 2, 3 ... 10, J, Q, K.
• Same rank is a free pass. If the next card ties the current one, you don't gain or lose anything and your streak carries on.
• If there are no higher cards left at all, the Higher button switches off (and the same goes for Lower). If only same-rank cards remain, either button works.

Scoring: meters, boost and shields

Every right call is worth a base of 20 meters, scaled by how risky the call was. A safe call (say, Lower on a King) pays close to 20. A long shot pays a lot more, because the base is divided by the chance of the call coming true. The odds are worked out from the cards actually left in the deck, so they shift as the run goes on.

On top of that is the boost. Your first right call in a flight is x1, the next x2, then x3, and so on up to x10. Ties keep the boost going. Banking or crashing resets it to x1.

Get five right in a row and you earn a shield. The next time you're wrong, the shield pops instead of the rocket. You keep your meters in the air, but the boost goes back to x1. You can only carry one shield at a time, and another one comes at your next five-in-a-row.

Sky layers

As a single flight climbs, you pass through eight sky layers. Reaching one for the first time earns a Sky Stamp.

Controls (phone and computer)

On a phone or tablet, tap Higher, Lower or Bank at the bottom of the screen. On a computer you can click or use the keyboard.

Daily Deck and leaderboards

Launch! plays a fresh random shuffle every time. The Daily Deck gives everyone the same shuffle for the day, so you and your friends face exactly the same cards. Play it daily to keep a day streak going, and check the leaderboard from the trophy on the results screen (signed-in players can post scores for both modes).

Hangar: rockets, stamps and card backs

The Hangar holds your rockets and your Sky Stamps. New rockets unlock as your lifetime banked meters add up across every run:

You also earn card backs, which are shared with every card game on our site. They come for your first run, your first 3,000 meter score, and the first time a flight reaches Orbit, The Moon and the Nebula.

Tips and strategy

• Watch the strip. The bar above the cards shows how many of each rank are left in the deck. This is the whole game. A 7 is a coin flip early on, but if most of the high cards are gone it's an easy Lower.
• The percentage counts ties as safe. The number on each button includes same-rank cards, because a tie can't hurt you.
• Bank before a coin flip, not after. When the next call is close to 50 percent and you've got a big flight going, that's the moment to bank. Easy calls near 90 percent are where you let the boost run.
• Respect the boost. At x6 or x7, even a safe call pays well over 100 meters. Long flights are where the big scores come from, so don't bank every two cards.
• A shield changes the math. With a shield up, a wrong call only costs you the boost, so you can afford to push a little further or take a riskier call for more meters.
• Late in the deck, count. With ten cards left, the strip tells you almost exactly what's coming. Some of the best flights happen right at the end.
• For stamps, think flight, not run. Sky Stamps need the height in one flight, so if you're hunting The Moon at 1,600 m, you'll have to ride a hot streak and hold your nerve.

If you like pushing your luck with a deck, our Twenty-One Club is a good next stop.

Questions