Ariari (Open Tanyao & Atozuke Allowed) - Modern Standard Rules

What is Ariari?

Ariari is a rule setting where both kuitan (open tanyao) and atozuke (late yaku attachment) are allowed. It’s the dominant rule in modern mahjong, making the game more accessible for beginners with faster-paced gameplay.

Kuitan allows tanyao even with called tiles, and atozuke lets you call without having a confirmed yaku, attaching one later.

Rule Components

Rule	Description	Effect
Kuitan	Tanyao valid with calls	Easier to win
Atozuke	Can call without yaku	Easier to call

Rule Combinations

Name	Kuitan	Atozuke	Difficulty
Ariari	Yes	Yes	Easiest
Arinashi	Yes	No	Medium
Nashiari	No	Yes	Medium
Nashinashi	No	No	Hardest

Kuitan Rule

Open Tanyao

With kuitan allowed:
Call tiles → Still tanyao eligible
↓
All simple tiles (2-8)
↓
Valid 1 han yaku

Example Hand

Chi: 234m
Hand: 456p 678s 345s 55p

→ All simples, tanyao 1 han valid

Atozuke Rule

What Atozuke Means

Can call without confirmed yaku at call time
As long as final hand has yaku, you can win
Greater calling freedom

Example Sequence

1. Chi 567p (no yaku yet)
2. Continue building
3. Eventually complete tanyao
4. Win is valid

Ariari Advantages

Beginner-Friendly

Benefit	Description	Impact
Easy calling	No yaku needed to call	Hand progresses
More wins	Tanyao always available	More chances
Simple rules	Easy to understand	Quick to learn

Game Flow

Easy to call
↓
Fast-paced games
↓
More wins
↓
Fun gameplay

Ariari Disadvantages

Reduced Closed Hand Value

Closed hands less advantaged
- Calling often better
- Riichi value relatively lower
More luck factor
- Starting hand matters more
- Skill impact slightly reduced
Defense harder
- Opponents call more
- Harder to defend

Ariari Strategy

Basic Approach

Active calling
- Target tanyao
- Speed priority
Attach yaku later
- Call first
- Figure out yaku later
Balance with defense
- Aggressive but careful
- Avoid deal-ins

Calling Decisions

Situation	Decision	Reason
Good shape ready	Call actively	Tenpai is close
No yaku yet	Call is OK	Attach later
Low value	Consider closed	Aim higher

Adoption Status

General Parlors

Adopted by most parlors
Modern mahjong standard
Beginner-friendly

Competitive Mahjong

Organization	Rule	Notes
M-League	Ariari	Standard
Most leagues	Ariari	Common
Some groups	Arinashi	Stricter

Online Mahjong

Nearly all use ariari
Sometimes configurable
Default setting

Regional Differences

Region	Rule	Notes
Kanto	Ariari	Standard
Kansai	Ariari	Mainstream
Some areas	Nashinashi	Traditional

Common Mistakes

Not checking rules
- Always confirm before play
- Regional differences exist
Misunderstanding atozuke
- OK to call without yaku
- Just need yaku by end
Forgetting kuisagari
- Some yaku lose han when called
- Calculate correctly
Confusing with sakizuke
- Sakizuke = atozuke NOT allowed
- Opposite meaning

Kuitan: Open tanyao
Atozuke: Late yaku attachment
Nashinashi: Opposite rule set
Tanyao: All simples yaku

Summary

Ariari means both kuitan and atozuke are allowed - the standard in modern mahjong. Tanyao is valid even with calls, and you can call without a confirmed yaku as long as you have one by the time you win. This makes the game more accessible and fast-paced. Always confirm the rules before playing, as some places still use stricter settings. Understanding ariari helps you play more actively and enjoy more wins.