First Tuna Auction (鮪魚初競)

First Tuna Auction

A New Year dawn at the fish market, rows of bluefin resting in the ice mist — the auction bell rings and the bids start climbing.

First Tuna Auction is a 6×5 tumbling slot set at the year's first tuna auction. 8+ matching symbols pay anywhere; auction bells trigger free spins with accumulating otoro multipliers.

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Demo play uses virtual credits with no monetary value.

RTP: 96.70%
Volatility: High11.20
Max win: 5,000× bet
Bonus buy: 100× bet

In-game screens

Captured straight from the running game — real boards, real wins.

First Tuna Auction — Base game — **Base game**A 6 × 5 board. Matching symbols pay anywhere on it.

First Tuna Auction — Cascading win — **Cascading win**Winning lots rest on a bed of crushed ice, freeze for a beat and shatter; one flies to the bidders, new ones drop in, and a single spin can pay several times.

First Tuna Auction — Free spins — **Free spins**In the New Year auction hall, the collected multiplier accumulates for the whole feature and applies to every later win.

First Tuna Auction — Big win — **Big win**A single round is capped at 5,000× the bet.

First Tuna Auction — Bonus buy — **Bonus buy**Buy straight into free spins for 100× the bet. Buy RTP is measured separately.

First Tuna Auction — In-game paytable — **In-game paytable**The same game definition as the table on this page: the game receives it from the server, and this page reads it at build time.

Specification

Type	6 × 5 tumble, scatter pays (no paylines)
Return to player (RTP)	96.70%
Bonus buy RTP	96.41%
Volatility	High (11.20)
Hit rate	48.97%
Max win per round	5,000× bet
Free spins frequency	≈ 1 in 214.68 spins
Calibration sample	2,240,000,000 spins, standard error 0.02%

Game math specifications and the paytable are read at build time from the definitions shared with the server code. See Math version for the configuration shown; confirm any other version or operator-specific settings separately.

How wins work

A 6 × 5 board. 8 or more matching symbols anywhere on it pay — no paylines, no adjacency requirement.
Winning symbols clear and new ones drop in from above, so a single spin can chain several wins.
Each win = (bet ÷ 20) × symbol multiplier × active multiplier.
As a rule, at most 2 of the same symbol appear per column, which prevents full-column stacking and keeps clusters spread across the board.

Paytable

Values are the symbol multiplier in: win = (bet ÷ 20) × symbol multiplier × active multiplier.

Symbol	8–9	10–11	12+
Bluefin tunaHigh-pay	200	500	1000
Tail cross-sectionHigh-pay	50	200	500
Ice crateHigh-pay	40	100	300
Hand hookHigh-pay	30	40	240
Crushed iceLow-pay	20	30	200
Inspection torchLow-pay	16	24	160
Rubber bootsLow-pay	10	20	100
Insulated glovesLow-pay	8	18	80
Auction ledgerLow-pay	5	15	40

Special symbols

Auction bell (scatter)

No lines, no adjacency — 4 anywhere on the board trigger the free spins feature.

Otoro

Counts when a win lands. Base game ×2–×20, free spins ×2–×500.

Features

Otoro (multipliers)

Counted only when a win lands; the number on the otoro block is the multiplier. Base game ×2 – ×20. Otoro on the board when a win lands are summed and applied to that cascade's win; they do not carry across cascades.

Free spins

4 auction bells award 15 spins in the New Year auction hall. Otoro in free spins run ×2 – ×500, and the collected multiplier accumulates for the whole feature, applying to the current and every subsequent win.

Retrigger

3 more auction bells during free spins add 5 spins, with the accumulated multiplier carried over.

Bonus buy

Buy directly into free spins for 100× the bet. Bonus buy RTP (96.41%) is measured separately from the base game.

Dry-spin rescue

After 15 consecutive rounds paying less than 1× the bet, the next spin is topped up to a cluster of 8 low-pay symbols — and so is every spin after it until a round pays at least the bet. Only completed rounds still queryable in the live system count; earlier progress may no longer be retained after a long absence. The rescued spin's bet may not exceed the lowest bet of those 15 rounds; at a higher bet that spin is not topped up. Base game only; bonus buys do not count. The RTP in the spec table assumes continuous play of this game at one bet size and includes this feature's contribution (about 2.66 percentage points).

Technical

Game code	aki_hatsuseri
Math version	v96
Technology	HTML5, no plug-in; one client for desktop and mobile
Viewport	Landscape with proportional scaling
In-game language	Traditional Chinese (additional languages on request)
Currencies	TWD (others can be registered on request)
Integration	Transfer wallet (Operator API v3), launch-token redirect

Sources & verification scope

This product specification is written and maintained by its developer, Akitsora Gaming (AKI電子 in Taiwan). Measurement methods and sample information for RTP, volatility and hit rate appear in the specification table. Sampled results have uncertainty; RTP describes long-run return, not an individual player or session outcome.

Internal simulations and tests are not independent certification. We do not currently hold GLI or BMM certification reports. Supply to a market requiring third-party certification depends on completing its requirements.

See slot game development and supply for integration and supply scope, About us for development and content responsibility, or contact us for a math summary, version confirmation or a correction to this page.

The story

Fiction and adapted settings written by Akitsora Gaming for this title, including invented dialogue and events. This is not a historical or folklore reference. The rules and specification tables define the gameplay and math.

The year's first auction always begins before dawn.

I. Fish in the ice mist

A row of cold white lamps comes on overhead. On the wet floor, bluefin lie in neat rows on crushed ice.

Buyers walk the rows with torches: the silver of the body and the red of the tail cut are the year's fortune.

II. Otoro

The number on a falling otoro block, marbled fine as frost, is the weight of the spin (base game ×2 to ×20).

III. The opening bell

When 4 auction bells ring together, the auctioneer steps up on his stand with the bell held high and every hand in the hall goes up. Over the next 15 spins the bids keep climbing (×2 to ×500).

3 more bells add 5 more spins.

IV. Sold

The bell falls silent and the auctioneer points — the first fish of the year has found its owner.

Want to spin First Tuna Auction yourself?

The demo needs no account — click and spin. For integration docs, the math summary or sandbox access, send us an email.

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Demo play uses virtual credits with no monetary value.

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