Kabe: Difference between revisions

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'''Kabe''' {{kana|壁}} takes into account the number of tiles available (or unavailable) for tile groups, such as [[shuntsu|sequences]] and [[koutsu|triplets]].  Both [[tile efficiency]] and [[defense]] are in consideration. In the case of tile efficiency, certain tiles may not be available; or they're available in fewer number. As for defense, visible tiles may help indicate and deduce which tiles are safer to discard than others.  Of course, this technique may or may not effectively deduce [[genbutsu|100% safe tiles]].  Kabe effectively eliminates the [[ryanmen]] wait around the particular number tile, but other tile waits still apply.
'''Kabe''' {{kana|壁}} 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.


== Visible tiles ==
Taking note of kabe can also help with [[tile efficiency]]. As tiles are played, it becomes less likely for you to draw said tiles.
All tiles shown in the [[discard pile|discards]], [[dora]] indicator(s), and even one's own hand. These tiles are noted as "visible tiles".  Players take into account, that every tile type has three copies plus its own.  In other words, for every tile, there are four of them.  With that in mind, for each specific tile type, players can keep track of how many are left available, as the discard piles grow, along with the tiles in the hand.


=== Kan ===
== Visible Tiles ==
{{main|Kan}}
Visible tiles include:
*Tiles in the [[discard pile|discards]]
*Tiles in the [[dora]] indicator(s)
*Tiles in your own hand
*Tiles [[Naki|used for your opponent's tile calls]]


[[Naki|Calls]] for kan have an astute effect on kabe, as this tile call requires all four of a single tile type. So immediately, this renders particular tiles as unavailable to the other players.
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.


== One chance ==
A call for [[kan]] automatically reveals 4 tiles, so kan calls are particularly subject to kabe.
'''One chance''' is an idea behind kabe.  Here, players make use of 3 out of 4 of particular tiles as a means to judge tile safety.  This means, if a player is looking to form a ryanmen wait around that particular tile, then the player has the very last one.  For other players, the chance of deeming safety around those tiles is decent, but it is by no means 100%.  Tiles surrounding the one chance is certainly better than live tiles with no read what-so-ever.


== No chance ==
== Defense ==
'''No chance''' is another idea behind kabe.  Here, players make use of all 4 of particular numbered tiles as a means to judge tile safety.  This means  tiles surrounding that number tile can no longer deal into a ryanmen wait. For example:
Kabe does not make a tile [[genbutsu|100% safe]], but it can help determine which tiles are less likely to deal in.
1 for 2, 12 for 3, 23 for 4, 37 for 5, 78 for 6, 89 for 7, and 9 for 8.


== Usage ==
===No chance===
By taking note on the unavailablity of certain tiles, then one can deduce the impossibility or less likelihood of certain [[mentsu|tile groups]] to form.  For example, when two of a type type are visible, then another player cannot form triplets.  This is particularly true for [[jihai|honor tiles]].  The same logic may be applied to sequences. The unavailability of certain numbered tiles increases the difficulty in forming certain numbered sequences.
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.


As a consequence, the unavailability of certain tiles may hinder one's hand from either [[tenpai]], [[agari|completion]], or even forming 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.
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: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.


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.
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).
=== 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.
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).
=== Usage ===
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.
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.
== 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.
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.


==External links==
==External links==

Latest revision as of 10:35, 9 June 2024

Kabe 「壁」 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.

Taking note of kabe can also help with tile efficiency. As tiles are played, it becomes less likely for you to draw said tiles.

Visible Tiles

Visible tiles include:

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.

A call for kan automatically reveals 4 tiles, so kan calls are particularly subject to 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

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.

For example, if all four 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:

  • (Waiting for: and )
  • (Waiting for: and )
  • (Waiting for: )

Therefore, and 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.

Regarding and , 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 () and () respectively. These tiles are not considered "no chance" - there's still a chance they have a sequence-based wait.

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).

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.

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).

Usage

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.

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.

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, 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.

External links