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Hey! You know how everything kinda sucks?

Sure you do. You go through life, and it's all just kinda crappy, food doesn't taste good, the air smells stale, everyone looks glum and dumpy. Aren't you sick of this?

Don't you want to know why it's like that? Because you can't always play Sumo! Well, we here at Stinkbot are in the business of candle lighting, not darkness cursing. We've figured out a way to let you play Sumo! All the time!

Sumo! for iPhone

How? With your iPhone, silly! You know, your iPhone, that small handheld computer you used for about a week and then lost under a pile of laundry and old dishes and wadded newspaper? Dig it out! Because you can now play Sumo! On your iPhone! Hot damn! Everything's starting to look all right!

Sumo! for iPhone

(Click to enlarge)

What is Sumo?

Sumo! is a fast-moving game of strategy we originally created as a Shockwave game in 1997. It was featured in Wired magazine and had millions of players for both its single-player and multiplayer versions. We later made a half-assed version for the Palm OS. For its tenth birthday, we dug it up, dusted it off, rewrote it in Objective-C, prettied it up, and now we're giving it to you!

How to Play

Defeat the opposing sumo wrestler ("Rikishi") by knocking him off the bridge ("dohyo", fighting space). You can also win by being furthest advanced on the dohyo when the last tile is drawn. There's a deck of numbered tiles, like playing cards. Each player has five tiles in their hand. Players alternate playing tiles to move or attack until a Rikishi is knocked off the dohyo or the draw pile is exhausted. You can attack with multiple tiles to increase the intensity of the attck.

Complete Rules

Sumo is a 2-player strategy game of battling Rikishi (sumo wrestlers). The board shows a dohyo (fighting space) consisting of 23 spaces, or 'planks'. The Rikishi (sumo wrestlers) begin each bout at opposite ends of the dohyo and fight until one has knocked the other off the end of the dohyo, or until the 'deck' of thirty tiles is exhausted. Points are awarded for successful attacks and for being the furthest advanced at the end of each bout. The game is played over several bouts. The first to reach 80 points is the winner.

Glossary & Screen Layout


The game controls are the buttons above your hand labelled 'retreat', 'advance', and 'attack'. To use them, click the button with the mouse after you have selected the tile(s) you wish to play.


The deck consists of thirty numbered tiles, five tiles each numbered 0 through 5 (five '0's, five '1's, and so on). The draw pile for this deck is represented by a single tile in the upper right-hand corner. The number below this tile shows the number of tiles remaining in the draw pile. Watch this number to see how close you are to the end of the bout! To the left of the draw pile is the discard pile, which shows the last tile played.


The dohyo (fighting space) consists of 23 spaces. The colored space or 'plank' on each end is where the rikishi start each bout. The color of the planks does not affect game play.


Your hand of tiles, usually five in number, is displayed along the bottom left of the screen. To select a tile, click on it with the mouse.

message window

Message windows appear to announce to announce successful attacks, the end of the bout, and when you try and do something not allowed by the rules. Click anywhere to make it go away.

opponent's hand

Your opponent's hand of tiles is displayed along the top of the screen. You don't get to see these until they are played.


Each player controls one Rikishi (sumo wrestler) which moves on the dohyo. One is blue, the other is red.


The score is displayed along the bottom of the screen. Bouts are played until one player reaches 80 points.

submit score

Clicking on the submit score button submits your score to the high score list. Note that your score is updated at the end of each match only and that submitting a score restarts the game from scratch.


The pinnacle of active sumo, yokozuna is the rank of grand champion. Only 65 men have held this rank since modern sumo's formalization in 1927.


All sumo bouts end with one of seventy winning techniques or two inadvertant methods called kimarite. Yori-kiri is the most commonly used kimarite consisting of pushing your opponent out of the dohyo with your body.


At the start of each bout, each player is dealt a hand of five random tiles and the Rikishi are placed at opposite ends of the dohyo. The Human Rikishi always starts the first bout, the start player alternates thereafter in every subsequent bout.

Players alternate playing. The player whose turn it is to play chooses to either move or attack and plays the appropriate tile(s) from their hand. If the player chooses to move, their Rikishi moves that many spaces forward or backward. If the player chooses to attack, the attack is resolved. When this is done, the player's turn ends and they are dealt enough new tiles to bring their hand back up to five.


To move, select a SINGLE tile from your hand by clicking on it with the mouse, then click 'Advance' or 'Retreat'. Your Rikishi will advance or retreat the number of spaces indicated on the tile. You cannot advance onto or through your opponent, and you cannot move off the end of the dohyo.


You can attack if you can play a tile that will move you directly on top of your opponent. Simply select the tile then click 'Attack'. If you wish to make a stronger attack, use more than one tile that MATCH the first. To attack with more than one tile, select ALL of the matching tiles you wish to use in the attack, THEN click 'Attack'.

Example #1:

If you are four spaces away from your opponent and you have a '4' tile in your hand, you can attack by selecting your '4' tile, then clicking 'Attack'.

Example #2:

If you are three spaces away from your opponent and have two '3's in your hand, you may attack with one or both '3's by selecting one or both '3's, then clicking 'Attack'. Attacking with both '3's is a stronger attack (see defending, below).


After each attack, the defender has a chance to block or 'reverse' the attack by immediately playing tiles from their hand that MATCH the tiles played in the attack EXACTLY. If the defender cannot match the attack tiles, the attack is successful.

Example #1:

Player A and player B are one space away from each other. Player A attacks with a '1'. To defend successfully, player B must play a '1' from their hand.

Example #2:

Player A and player B are three spaces away from each other. Player A attacks with two '3's. To defend successfully, player B must play two '3's from their hand.

IMPORTANT: Defending tiles are played for you automatically by the computer--you never select them yourself. After a successful defense you DO NOT draw to fill your hand, so will have to play your next turn with fewer tiles in your hand. After the end of your next turn, your hand will be filled as normal.

Successful Attack Results

When an attack is successful, the attacker moves the space occupied by the defender at the start of the turn. The defender is thrown back a number of spaces related to the strength of the attack--the stronger the attack and the fewer cards the defender has to block with, the further the defender is thrown.

For those interested few, the exact number of spaces is:
6 + [(sum of attack cards) - (sum of defense cards)]/2 (round up).

Or, for those fun-loving mathematicians out there it's:
6 + [AttackRange]/2 + [AttackRange] mod 2 + 6,
where AttackRange = [(sum of attack cards) - (sum of defense cards)]. Whew.

Example #1:

Player A attacks with two '3's. Player B has no '3's. Player B is thrown back 6 + [(3+3) - 0]/2 = 9 spaces. If player B had one '3', they would be thrown back 6 + [(3+3) - 3]/2 = 8 spaces (round up).

Example #2:

Player A attacks attacks with three '1's. Player B defends with two '1's and is thrown back 6 + [(1+1+1) - (1+1)]/2 = 7 spaces.

Successful Defense Results

When an attack is blocked or 'reversed', the attacker and defender remain in the positions they occupied at the beginning of the turn.

Ending a Bout

A bout ends when:

  • One player is forced off the end of the dohyo by an attack.
  • A player cannot move or attack one their turn (usually because they are pinned near their starting position by their opponent).
  • The last tile is drawn from draw pile.

If the bout ends due to the drawing of the last tile, the player who did not get the last tile has an opportunity for one last ATTACK before the end of the game. If the player cannot attack, the bout is over. This has the effect of balancing the last turn--it means the player who moves last (and therefore raws the last tile) must face a potential attack if they move within attack range.


Points are awarded for successful attacks and dohyo position as follows:

  • 5 points for a successful attack.
  • 10 points for an attack that knocks the opponent off the dohyo.
  • N points for the player who has advanced the furthest from their starting position when the bout ends, where N is the number of planks advanced including the starting space.
  • No points are awarded for position if the players have advanced the same amount at the bout's end.


Player A wins the bout by knocking Player B off the end. Player A is standing on plank 15, counted from their starting position. Player A is awarded 10 points for the attack, and 15 for position.


Bouts are played and points are accumulated by both players until the score of one or both players exceeds 80 points. When the current bout is completed, the highest score wins the match. In the unlikely event of a tie, the match remains a tie.

Total Score

Your total score is updated after each MATCH and is equal to:

Your point total (since you started playing)


Your opponent's point total (since you started playing)

You may submit your score to the high score list at any time. Submitting your score resets your score to zero and restarts any game in progress.


  1. In the beginning of the game, play your highest cards to advance quickly towards the center of the dohyo. Many bouts are decided by position, so it's important to get off to a good start.
  2. Try to keep at least one pair of cards in your hand so you have at least one favorable attack/defense range.
  3. It's safest to move within attack ranges for which you have multiple cards. That way, if you're attacked you can probably defend successfully and possibly even attack back when it's your turn.
  4. An attack with three cards cannot be defended against. It's a sure thing since there's only five cards of each type. But holding three of anything limits your movement options, so sometimes it's good to dump one and keep the pair.
  5. Count those cards! If you know there are only two '2's left in the game and you have one of them in your hand, you can safely move within two--at most your opponent can attack with one '2', which you can then defend.
  6. It's risky to move within an attack range if you have no cards to defend yourself, unless you know that all of those cards have been played already. Still, it can sometimes bluff your opponent and make them back up.
  7. Multiple '1's are quite powerful. Advance within one and your opponent must attack or back up. The strength of '1's are balanced, however, by the fact that the opponent won't be thrown very far if the attack succeeds.
  8. Use '0's to not move and stay at a favorable attack range.
  9. Watch out for attacks from '4's and '5's. A successful attack with even a single card can throw you quite a ways.

Real Sumo

Want to learn about the real sport of sumo? The excellent SumoWeb! site will get you started.

Free updates for registered users! When we figure out how you can register, we'll let you know here.

* It's actually not at all exclusive. The Shockwave game can be played here, and there is a downloadable version for Palm OS here.