Kabe: Difference between revisions

Revision as of 16:33, 19 February 2025

Kabe 「壁」 (lit. "wall", also called "blockade") is a defensive tactic that takes into account the number of tiles available.

If you can see all four copies of that tile, an opponent can never have that tile.
If you can see multiple copies of a tile, then an opponent is less likely to have that specific tile.

When multiple/all copies of a tile are visible, the same-suit tiles up to +/- 2 away, and towards the outside (away from 5), become safer.

Visible Tiles

"Visible tiles" are tiles you can see, and thus know aren't in an opponent's hand. These include:

Tiles in the discards
Tiles in the dora indicator(s)
Tiles in your own hand
Tiles used for your opponent's tile calls

For example, a call for kan reveals 4 tiles, which can immediately be used for kabe.

Defense

Kabe does not make a tile 100% safe, but it can help determine which tiles are less likely to deal in.

No chance

No chance occurs when all four tiles of a tile are visible, which means that no copies of that tile can be hidden in an opponent's hand. This makes certain hand compositions become impossible. Therefore, tiles towards the outside (up to +/- 2 away) become safer.

For example, if all four 3-pin are visible, it is impossible for an opponent to have 3-pin, making it impossible for an opponent to have a wait pattern of:

Pattern	Waiting for	Pattern	Waiting for

Overall, with all 3-pin visible:

and are much safer than normal, since it's impossible for an opponent to have a ryanmen or kanchan wait on those tiles.

and are only a bit safer than normal, since an opponent can have a ryanmen wait (56-pin or 67-pin in hand) on those tiles. They are still quite dangerous.

Kabe works on tiles towards the outside, up to +/- 2 away from the all-visible tile. E.g., if all four 4-pin are visible, 2-pin and 3-pin are safer but 1-pin is not.

Kabe can be combined with other kabe or suji to eliminate ryanmen waits. For example, with all four 3-sou and 7-sou visible, 5-sou is safer. Similarly, if all four 4-pin are visible and an opponent discards 9-pin, the 6-pin is safer against that opponent (45-pin in hand impossible due to kabe, 78-pin in hand would be furiten due to 9 discard).

One chance

One chance occurs when three copies of a tile are visible. The concept works like no chance: when three copies are visible, then it is less likely (but still possible) for an opponent to have the fourth copy hidden in their hand. For example, if you can see three copies of 3-pin, then 1-pin and 2-pin are less likely to be an opponent's winning tile.

A one chance tile is less safe than no chance, but still safer than a regular tile. However, one chance becomes more dangerous as the game progresses (since it becomes more likely that the 4th copy of the tile is in the opponent's hand).

Double one chance

Double one chance occurs when there are three copies visible of two types tiles. For example, if three 3-pin are visible and three 2-pin are visible, double one chance applies to 1-pin. Double one chance is less safe than no chance but safer than once chance.

Safety

No chance is as safe or safer than suji, since no chance prevents ryanmen and kanchan waits, while a suji tile is only immune against ryanmen waits. In addition, kabe applies to all players, while suji only works on specific players. However, since kabe is relatively rare, both defensive techniques should be use

One chance tiles are less safe than suji. One chance becomes very dangerous in the late game, since it becomes likely for an opponent to have the last copy of a tile.

Like suji, kabe implies that an opponent has a ryanmen (or kanchan) wait. So if an opponent is going for a hand like toitoi or chiitoitsu, the usual rules of kabe don't apply. Instead, if you are certain an opponent is going for a pair/triplet hand, rely on tiles that have all 4 copies visible.

Tile Efficiency

While "kabe" usually refers to the defensive practice, looking at the visible tiles is important for tile efficiency.

By counting the number of visible copies of a tile, you can deduce how likely a certain tile group is to form. For example, when two of a type type are visible, then no other player can form a triplet. This particularly applies with honor tiles. The same logic may be applied to sequences; e.g. as 3-man tiles become visible, completing a 12-man penchan becomes less likely.

Thus, it may hinder a player's hand from reaching tenpai, winning, or having certain yaku. This is particularly the case for yakuman. In the case of kokushi musou, if all four of a tile type required for that yakuman, then the possibility for any player completing the hand is completely nullified.

External links

@@ Line 1: / Line 1: @@
-'''Kabe''' {{kana|壁}} (lit. "wall") is a defensive tactic that takes into account the number of tiles available. If you can see multiple copies of a tile, then an opponent is less likely to have that specific tile. If you can see all four copies of that tile, an opponent can never have that tile. This fact makes other nearby tiles safer to discard.
+'''Kabe''' {{kana|壁}} (lit. "wall", also called "blockade") is a defensive tactic that takes into account the number of tiles available.
+* If you can see all four copies of that tile, an opponent can never have that tile.
+* If you can see multiple copies of a tile, then an opponent is less likely to have that specific tile.
-Taking note of kabe can also help with [[tile efficiency]]. As tiles are played, it becomes less likely for you to draw said tiles.
+When multiple/all copies of a tile are visible, the same-suit tiles up to +/- 2 away, and towards the outside (away from 5), become safer.
 == Visible Tiles ==
-Visible tiles include:
+"Visible tiles" are tiles you can see, and thus know aren't in an opponent's hand. These include:
 *Tiles in the [[discard pile|discards]]
 *Tiles in the [[dora]] indicator(s)
@@ Line 10: / Line 12: @@
 *Tiles [[Naki|used for your opponent's tile calls]]
-Only four copies of a tile exist. So if most or all of the copies of a tile are visible, then you can gain information about the other players' hands.
+For example, a call for [[kan]] reveals 4 tiles, which can immediately be used for kabe.
-A call for [[kan]] automatically reveals 4 tiles, so kan calls are particularly subject to kabe.
 == Defense ==
 Kabe does not make a tile [[genbutsu|100% safe]], but it can help determine which tiles are less likely to deal in.
-===No chance===
+=== No chance ===
-If all four copies of a tile are visible, then no copies of that tile can be hidden inside an opponent's hand. Thus, certain hand compositions become impossible.
+'''No chance''' occurs when all four tiles of a tile are visible, which means that no copies of that tile can be hidden in an opponent's hand. This makes certain hand compositions become impossible. Therefore, tiles towards the outside (up to +/- 2 away) become safer.
+For example, if all four 3-pin are visible, it is impossible for an opponent to have 3-pin, making it impossible for an opponent to have a [[wait]] pattern of:
+{| class=wikitable
+! Pattern !! Waiting for !! Pattern !! Waiting for
+|-
+| {{#mjt:23p}} || {{#mjt:14p}} || {{#mjt:34p}} || {{#mjt:25p}}
+|-
+| {{#mjt:13p}} || {{#mjt:2p}}
+|}
+Overall, with all 3-pin visible:
-For example, if all four {{#mjt:3p}} are visible, then it is impossible for an opponent to have 3-pin. Therefore, it is impossible for an opponent to have a [[wait]] pattern of:
+* {{#mjt:1p}} and {{#mjt:2p}} are much safer than normal, since it's ''impossible'' for an opponent to have a [[ryanmen]] or [[kanchan]] wait on those tiles.
-*{{#mjt:23p}} (Waiting for: {{#mjt:1p}} and {{#mjt:4p}})
-*{{#mjt:34p}} (Waiting for: {{#mjt:2p}} and {{#mjt:5p}})
-*{{#mjt:13p}} (Waiting for: {{#mjt:2p}})
-Therefore, {{#mjt:1p}} and {{#mjt:2p}} are much safer than normal - these are considered "no chance" tiles. It is impossible for an opponent to complete a sequence with these tiles. It is still possible for an opponent to win off a [[shanpon]] (triplet wait) or [[tanki]] (pair wait), though these types of wait are considerably rarer.
+* {{#mjt:4p}} and {{#mjt:5p}} are only a bit safer than normal, since an opponent can have a ryanmen wait (56-pin or 67-pin in hand) on those tiles. They are still quite dangerous.
-Regarding {{#mjt:4p}} and {{#mjt:5p}}, these tiles are only a bit safer than normal. It is still possible for an opponent to have a sequence wait on these tiles, such as ({{#mjt:56p}}) and ({{#mjt:67p}}) respectively. These tiles are not considered "no chance" - there's still a chance they have a sequence-based wait.
+Kabe works on tiles towards the outside, up to +/- 2 away from the all-visible tile. E.g., if all four 4-pin are visible, 2-pin and 3-pin are safer but 1-pin is not.
-In general: if all four copies of a numbered tile are visible, then any nearby tiles ''closer to the end'' become safer. So a kabe of 4-pin would make 2-pin and 3-pin no chance tiles; a kabe of 2-pin would make 1-pin a no chance tile. Also, having two kinds of kabe will make certain tiles in-between safer: a kabe of 3-pin and 7-pin will make 5-pin safer (but not 4-pin or 6-pin).
+Kabe can be combined with other kabe or [[suji]] to eliminate [[ryanmen]] waits. For example, with all four 3-sou and 7-sou visible, 5-sou is safer. Similarly, if all four 4-pin are visible and an opponent discards 9-pin, the 6-pin is safer against that opponent (45-pin in hand impossible due to kabe, 78-pin in hand would be [[furiten]] due to 9 discard).
 === One chance ===
-'''One chance''' occurs when three copies of a tile are visible. Otherwise, the concept is similar to no chance. That is, when three copies are visible, then it is less likely for an opponent to have the fourth copy hidden in their hand. For example, if you can see three copies of 3-pin, then 1p and 2p are less likely to be an opponent's winning tile.
+'''One chance''' occurs when three copies of a tile are visible. The concept works like no chance: when three copies are visible, then it is less likely (but still possible) for an opponent to have the fourth copy hidden in their hand. For example, if you can see three copies of 3-pin, then 1-pin and 2-pin are less likely to be an opponent's winning tile.
+A one chance tile is less safe than no chance, but still safer than a regular tile. However, one chance becomes more dangerous as the game progresses (since it becomes more likely that the 4th copy of the tile is in the opponent's hand).
-Of course, a one chance tile is less safe than no chance, but still safer than any random tile. However, one chance becomes more dangerous as the game progresses (since it becomes more likely that the 4th copy of the tile is in the opponent's hand).
+=== Double one chance ===
+'''Double one chance''' occurs when there are three copies visible of two types tiles. For example, if three 3-pin are visible and three 2-pin are visible, double one chance applies to 1-pin. Double one chance is less safe than no chance but safer than once chance.
-=== Usage ===
+=== Safety ===
-A no chance tile is usually safer than [[suji]]. A no chance tile is immune to [[ryanmen]] and [[kanchan]] waits, while a suji tile is only immune against ryanmen waits. In addition, kabe applies to all players, while suji has to be checked for each individual player. Of course, it is possible to apply both defensive techniques when defending against an opponent. One chance tiles are less safe than suji.
+No chance is as safe or safer than [[suji]], since no chance prevents [[ryanmen]] and [[kanchan]] waits, while a suji tile is only immune against ryanmen waits. In addition, kabe applies to all players, while suji only works on specific players. However, since kabe is relatively rare, both defensive techniques should be use
-Like suji, kabe implies that an opponent has a ryanmen (or kanchan) wait. So if an opponent is going for a hand like [[toitoi]] or [[chiitoitsu]], kabe doesn't apply.
+One chance tiles are less safe than suji. One chance becomes very dangerous in the late game, since it becomes likely for an opponent to have the last copy of a tile.
+Like suji, kabe implies that an opponent has a ryanmen (or kanchan) wait. So if an opponent is going for a hand like [[toitoi]] or [[chiitoitsu]], the usual rules of kabe don't apply. Instead, if you are certain an opponent is going for a pair/triplet hand, rely on tiles that have all 4 copies visible.
 == Tile Efficiency ==
-By counting the number of visible copies of a tile, you can deduce how likely a certain [[mentsu|tile group]] is to form. For example, when two of a type type are visible, then no other player can form a triplet. This particularly applies with [[jihai|honor tiles]].  The same logic may be applied to sequences; e.g. as 3-man tiles become visible, completing a 12-man [[penchan]] becomes less likely.
+While "kabe" usually refers to the defensive practice, looking at the visible tiles is important for [[tile efficiency]].
+By counting the number of visible copies of a tile, you can deduce how likely a certain [[mentsu|tile group]] is to form. For example, when two of a type type are visible, then no other player can form a triplet. This particularly applies with [[honor]] tiles.  The same logic may be applied to sequences; e.g. as 3-man tiles become visible, completing a 12-man [[penchan]] becomes less likely.
-Thus, it may hinder a player's hand from reaching [[tenpai]], [[agari|completing]], or having certain yaku. This is particularly the case for [[yakuman]].  In the case of [[kokushi musou]], if all four of a tile type required for that yakuman, then the possibility for any player completing the hand is completely nullified.
+Thus, it may hinder a player's hand from reaching [[tenpai]], winning, or having certain yaku. This is particularly the case for [[yakuman]]. In the case of [[kokushi musou]], if all four of a tile type required for that yakuman, then the possibility for any player completing the hand is completely nullified.
 ==External links==