Suukantsu

Suukantsu

Suukantsu (四槓子, すうかんつ) is one of the rarest yakuman hands, requiring four kans (quads of four identical tiles) plus one pair. You need four sets of four identical tiles—16 specific tiles from a 136-tile set—making it statistically one of the most difficult yakuman to achieve. Worth maximum yakuman points (8,000 base for non-dealer, 12,000 for dealer).

Detailed Explanation

Requirements

To achieve suukantsu, you must have:

• Four kans: Any combination of ankan (concealed), minkan (open), or shouminkan (added kan)
• One pair: The remaining two tiles form your pair

For example: 2-2-2-2 bamboo, 5-5-5-5 characters, 9-9-9-9 dots, East-East-East-East (four kans), plus a pair of 6-man.

Extreme Rarity

Suukantsu is legendarily rare:

• Tile requirements: Sixteen specific tiles (four each of four types) from a set where only four of each tile exist
• Draw probability: The statistical chance of collecting four complete sets of four tiles is infinitesimally small
• Opponent interference: If opponents call pon or kan on tiles you need, suukantsu becomes impossible

Most players never achieve suukantsu even after decades of play. Each occurrence is typically photographed and celebrated.

Fifth Kan Rule (Suukaikan)

In most rule sets, if a fifth kan is declared across all players (not just one player), the hand ends in an abortive draw called suukaikan. This rule prevents infinite kan chains.

Implication: If another player has already declared one or more kans, and you’re building suukantsu, be aware that your fourth kan might be the game’s fifth overall, triggering suukaikan and ending the hand without a winner.

Kandora Bonanza

Each kan reveals one new kandora indicator. Four kans mean four extra kandora indicators beyond the initial dora. While suukantsu alone scores yakuman, the additional kandora are irrelevant for scoring (yakuman is already maximum). However, they help other players, which is a strategic consideration when declaring kans.

Strategic Considerations

Mixing Kan Types: You can combine ankan, minkan, and shouminkan freely. Most suukantsu hands involve at least some minkan calls since self-drawing 16 specific tiles is virtually impossible.

Toitoi Structure: Suukantsu is technically a form of toitoi (all triplets/quads) since kans are four-tile extensions of triplets. However, yakuman overrides toitoi, so you score only yakuman.

Opponent Awareness: Once you’ve declared three kans, opponents realize suukantsu potential and may adjust their discards to avoid completing your hand.

Usage Example

In an extraordinarily lucky hand, you draw four 4-bamboo tiles and declare ankan. An opponent discards 7-characters when you hold three, so you call kan (minkan). Later, you self-draw four White dragons and declare ankan again. Finally, you draw four South winds over several turns and declare ankan. Your hand: 4-4-4-4 bamboo, 7-7-7-7 characters, White-White-White-White, South-South-South-South (four kans), plus any pair. You win and declare suukantsu (yakuman), scoring 8,000 base points (32,000 total for non-dealer) or 12,000 base points (48,000 total for dealer). Opponents marvel at the rarity, and you photograph the hand for posterity.

Related Terms

Sankantsu: Three kans yaku (2 han). One step below suukantsu.

Kan: A quad of four identical tiles. Suukantsu requires four kans.

Toitoi: All triplets yaku. Suukantsu is structurally a form of toitoi but scores yakuman instead.

Yakuman: The highest-value hand patterns. Suukantsu is one of the rarest yakuman.