Why Does My Mahjong Set Have Cat, Mouse, Rooster, and Worm Tiles?

Discover how Singapore mahjong animal tiles provide bonus points, special pair bonuses, and the famous passport rule!

If you’ve ever opened a mahjong set and discovered four unusual tiles featuring a Cat, Mouse, Rooster, and Worm, you may have wondered whether they actually belong in the game.

After all, most players are familiar with the three suits, winds, dragons, flowers, and seasons. Animal tiles seem completely out of place.

Yet these quirky tiles are not a mistake. They are an important part of Singapore mahjong and some Malaysian mahjong rules. In fact, animal tiles can be surprisingly powerful. Not only do they provide bonus points, but in Singapore mahjong, they can also act as a ‘passport,’ allowing certain hands to qualify for mahjong.

This unique rule helps distinguish Singapore mahjong from Chinese, Japanese, American, and many other mahjong variants.

Let’s take a closer look at what these tiles are, where they came from, and why experienced players are often happy to see them.

New to Singapore mahjong?

Animal tiles are just one of several unique features found in Singapore mahjong. If you’re learning the game, these beginner-friendly guides can help you understand scoring, tile meanings, and how Singapore rules differ from other mahjong variants.

– Singapore Mahjong Scoring Rules (Printable)
– Chinese Mahjong Guide: Hong Kong, Singapore, Shanghai & Taiwan
– Mahjong Scoring Systems Compared: Chinese, Japanese & American Variants
– Mahjong Variants (US, Chinese, Japanese) for Travel and Three Players

What Are the Four Animal Tiles?

A standard set of Singapore mahjong animal tiles contains four tiles:

• Cat
• Mouse (or Rat)
• Rooster (or Chicken)
• Worm (usually represented as a Centipede)

Unlike suit tiles, animal tiles are not used to form chows, pungs, kongs, or pairs. They are bonus tiles that are set aside when drawn.

When a player draws an animal tile, it is immediately exposed face-up beside their hand. The player then draws a replacement tile from the back end of the wall, ensuring they continue to hold the correct number of tiles.

Because animal tiles are displayed openly, all players can see who has collected them.

At first glance, they seem similar to flower and season tiles. However, animal tiles have additional scoring and qualification functions that make them much more significant.

Why Don’t Most Mahjong Variants Use Animal Tiles?

One reason animal tiles often surprise players is that they are not commonly found in many Chinese mahjong variants.

For example:

• Hong Kong Mahjong typically uses flowers but not animal tiles.
• Chinese Official Mahjong (MCR) does not use animal tiles.
• American mahjong does not use animal tiles.
• Japanese mahjong (riichi) does not use animal tiles.

Animal tiles are primarily associated with Singapore mahjong and some Malaysian mahjong rule sets.

Most Chinese mahjong sets instead include flower and season tiles, which provide bonus points but do not serve the same passport function found in Singapore mahjong.

This makes them a regional feature rather than a universal mahjong component.

Their inclusion reflects the way mahjong evolved as it spread throughout Asia. Different regions added their own rules, scoring systems, and bonus mechanics. Singapore mahjong became known for introducing several unique elements, with animal tiles being among the most recognizable.

As a result, players who purchase a Singaporean or Malaysian set often discover these unusual tiles and wonder what they are for.

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The Most Important Rule: Animal Tiles as a Passport

Although many players focus on the bonus points earned from animal tiles, their most important function in Singapore mahjong is often their role as a “passport.”

To understand why, it helps to know that Singapore mahjong generally requires a hand to meet certain qualification requirements before it can win.

A hand consisting of a mixture of chows (sequences) and pungs (triplets) may not automatically qualify.

This is where animal tiles become valuable. While scoring details vary between playing groups, the passport rule is one of the most distinctive features associated with Singapore mahjong.

In many Singapore mahjong rule sets, possessing an animal tile can act as a passport, helping a mixed hand containing both chows and pungs qualify for mahjong.

For example, imagine a player has:

• 3-4-5 Bamboo
• 6-7-8 Characters
• Red Dragon pung
• East Wind pung
• Pair of White Dragons

At first glance, this looks like a perfectly reasonable mahjong hand. However, depending on the rules being used, it may not meet the minimum requirements needed to declare mahjong.

In some situations, this hand may not satisfy qualification requirements on its own.

However, if the player has drawn an animal tile, it may serve as a passport, allowing the hand to qualify.

This rule creates an interesting strategic dynamic.

A flower tile might provide a small bonus. An animal tile might allow you to win the entire hand.

For that reason, experienced Singapore mahjong players often view animal tiles as much more than simple bonus tiles.

Printables

Animal Tiles Also Award Bonus Points

In addition to their passport function, Singapore mahjong animal tiles provide bonus payments.

The exact scoring system varies from table to table, but the general principle remains the same.

Each animal tile a player possesses can earn an additional payment from opponents. For example, a player who collects two animal tiles may receive a larger bonus than a player who collects only one, depending on the scoring rules being used.

These bonuses are separate from the scoring value of the winning hand itself.

As a result, animal tiles create a secondary layer of scoring that runs alongside the main game.

This helps explain why players are usually pleased to draw one.

Unlike many bonus mechanics in other mahjong variants, animal tiles provide both immediate and long-term benefits. They can help a hand qualify for mahjong through the passport rule while also contributing additional bonus payments during scoring.

Special Animal Pairs

The four animal tiles are not random.

They are arranged into two special predator-prey pairs:

• Cat + Mouse
• Rooster + Worm

Completing one of these pairs usually triggers an additional bonus.

Depending on the rules being used, this bonus may be awarded immediately when the second tile is drawn or during end-of-hand scoring.

The exact payout varies among playing groups and house rules.

These pair bonuses add another layer of excitement to drawing animal tiles. A player who already has a Cat may become especially interested in drawing the Mouse. Likewise, someone holding a Rooster will be hoping to find the Worm.

This creates a small collection game within the larger mahjong game.

The predator-prey theme also gives the animal tiles more personality than ordinary bonus tiles. Rather than simply collecting points, players are actively trying to complete meaningful pairs that can increase their winnings.

Chinese Mahjong Guide: Hong Kong, Singapore, Shanghai & Taiwan

Are Animal Tiles Good Luck or Good Strategy?

The answer is both.

Collecting all four animal tiles is relatively uncommon, but it does happen. Because there are only four animal tiles in the set, obtaining the complete collection is a memorable event.

Many Singapore mahjong groups award an additional bonus when a player possesses all four animals. Some tables treat this as a particularly valuable achievement and award a larger payout, while others simply stack the individual animal bonuses together with the pair bonuses. As with many aspects of Singapore mahjong, house rules may vary.

Regardless of the specific scoring method, drawing all four animal tiles is usually considered both lucky and profitable.

There is certainly an element of luck involved in drawing animal tiles. Players cannot control when they appear.

However, once an animal tile enters play, strategic considerations begin.

Players may:

• Benefit from passport qualification.
• Earn bonus payments.
• Complete predator-prey pairs.
• Pursue all four animals.
• Adjust hand-building decisions based on qualification requirements.

This combination of luck and strategy is one reason animal tiles remain popular among Singapore mahjong players.

They add excitement without significantly slowing down gameplay.

Most importantly, they create meaningful decisions rather than serving as simple decorative extras.

Final Thoughts

Animal tiles are one of the features that make Singapore mahjong instantly recognizable.

While they may look unusual to players accustomed to Chinese mahjong, Hong Kong mahjong, American mahjong, or Japanese mahjong, they play an important role in the game.

The Cat, Mouse, Rooster, and Worm tiles provide bonus points, create special pair combinations, and can even help a player qualify for mahjong through the passport rule.

That passport function is what truly sets them apart. In many Singapore mahjong rule sets, an animal tile is worth far more than a small scoring bonus because it can help an otherwise ineligible hand qualify to win.

So if you ever open a mahjong set and find four mysterious animal tiles tucked inside, you’ll know they are not novelty pieces. They are a distinctive part of Singapore mahjong tradition and one of the game’s most interesting regional innovations.

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Frequently Asked Questions

Q: What are the four animal tiles in mahjong?
A: The four animal tiles used in Singapore mahjong are Cat, Mouse (Rat), Rooster (Chicken), and Worm (Centipede).

Q: Are animal tiles used in Chinese mahjong?
A: Most Chinese mahjong variants do not use animal tiles. They are primarily associated with Singaporean and some Malaysian rules.

Q: What does the Cat and Mouse pair do?
A: The Cat and Mouse form a special predator-prey pair that usually awards an additional bonus when both are collected by the same player.

Q: What does the Rooster and Worm pair do?
A: Like the Cat and Mouse, the Rooster and Worm form a special predator-prey pair that typically earns an additional bonus when both are collected by the same player.

Q: What is a passport in Singapore mahjong?
A: A passport is a special qualification benefit provided by an animal tile. It allows certain mixed chow-and-pung hands to qualify for mahjong when they otherwise might not.

Q: Do animal tiles count as part of your hand?
A: No. Animal tiles are bonus tiles. They are exposed immediately and replaced with another draw (from the end of the wall).

Q: Can you win without animal tiles in Singapore mahjong?
A: Yes. Animal tiles are not required to win. However, they can help qualify certain hands and provide additional scoring opportunities.

Q: Are animal tiles used in American mahjong?
A: No. American mahjong does not use animal tiles. They are primarily found in Singaporean and Malaysian mahjong variants.

Written by Mahjong Playbook Editorial Team
Our guides are written and reviewed by mahjong enthusiasts with hands-on experience across multiple styles, including American, Chinese, and Japanese riichi. We focus on clarity, accuracy, and beginner-friendly explanations to help players learn with confidence.

Learn more about our editorial standards.