Rarestone Gaming

Koi Harmony

Single-line koi assembly game with a color-matching respin

SlotRanker Score

/ 99

05099

The SlotRanker Score is calculated from the visible data below. It is not affected by affiliate deals, and it cannot be bought.

How this score is built

RTP

96.47%

return to player

Volatility

Low/Medium

variance

Max win

888×

top multiplier

Min bet

$0.10

per spin

Reels

1 lines

Player rating

4.0 ★

2 votes

DEMO Play free, no signup

Rarestone Gaming

Embed on your site

4.0 / 5

2 ratings

User ratings are shown separately from the Slot Score unless stated otherwise.

Five weighted signals shape the composite. Four context signals refine ties. See how we rate for the full methodology.

Payouts & RTP9/10

RTP 96.47% → 9.0/10

Volatility6/10

low → 6.0/10

Win Potential5.9/10

x888.00 (888×) → 5.9/10

Features2/10

3 features → 2.0/10

Game Mechanics2.4/10

f=3 r=3 p=1 → 2.4/10

Context signals (tie-breakers)

Layout4/10

3x3 → 4.0/10

Bet Flexibility8/10

0.1–500 (×5000) → 8.0/10

Provider Reputation6.6/10

provider avg 6.6 → 6.6/10

Popularity2.5/10

synthetic proxy → 2.5/10

Popularity blends real player search demand (~30 markets) with a catalogue-derived proxy; games without measurable search demand use the proxy alone. Not live play telemetry.

Cite this score

SlotRanker Score: 53 — Koi Harmony by Rarestone Gaming

https://slotranker.com/rarestone-gaming/koi-harmony#score

How to cite

Slot Summary

Koi Harmony occupies the narrow space between a conventional line slot and a single assembly puzzle. Rarestone Gaming reduces play to three reels and one payline, asking each spin to form a complete koi from separate body sections. Low/Medium volatility and a 96.47% RTP support that restrained format, while rainbow segments introduce the only interruption: a respin in which every section shares one randomly chosen color.

How It Plays

Each spin presents three separate koi sections on one payline. A win requires those sections to align as a complete fish, with mixed and matching colors carrying different values.

The compact 3x3 layout leaves no secondary lines to inspect. Every result rests on whether the center payline creates a valid fish and which color that fish takes.

Theme & Atmosphere

Koi Harmony treats its Asia, Fish, Nature, and Sea themes as one quiet subject rather than several competing motifs. The pond setting keeps attention on the assembled koi.

The presentation matches the game's limited decision space. Instead of filling the screen with side features, Rarestone Gaming uses the fish itself as both the visual subject and paytable result.

Nature Fish Sea Asia

Features & Win Potential

Respins occur when a winning combination includes a rainbow segment. The awarded respin assigns one random color to every symbol, narrowing the outcome to a single matching-fish attempt.

The feature does not add reels, paylines, or a separate bonus screen. It briefly changes symbol behavior, then returns the game to its usual one-payline assembly task.

Respins Low/Medium 96% RTP

Spec sheet

Koi Harmony at a glance.

Identity

Slot nameKoi Harmony

StudioRarestone Gaming

Released6/24/2022

Math

SlotRanker Score53

RTP96.47%

VolatilityLow/Medium

Max win888×

Bet range$0.10 – $500.00

Player rating4.0 / 5 · 2 votes

Format

Reels1

Paylines1

Layout1x3

Features

Themes

Expected average based on this slot's 96.47% RTP — individual sessions vary with volatility.

Bet per spin

Spins per hour400

Session length (hours)

Cost per hour$1.41

Cost per session$1.41

Estimate only, for entertainment purposes — treat gambling as entertainment, not a way to make money, and set a budget you can afford to lose.

How long could a bankroll last on Koi Harmony? We simulate thousands of sessions from this game's published RTP and volatility — the long-run math, not a prediction of your next spin.

Bankroll ($)Bet per spin ($)Speed

Volatility tier: Medium-Low

Running simulation…

How this works

Each simulated spin either misses or returns a win drawn from a log-normal distribution, with the hit rate and spread set by the slot's volatility tier (Medium-Low). The model is calibrated so the average return equals this slot's published RTP (96.47%), with wins capped at its top multiplier (888×).

This is a simplified, parametric model of the game's math — not its real paytable. It exists to make the house edge visible over many sessions, so the numbers above are averages across thousands of runs, never a forecast of one.

This is math, not a prediction. Real sessions vary wildly, and no strategy changes a game's built-in house edge. Play for fun, set limits, and never bet more than you can afford to lose.

Where to play Koi Harmony

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Compare Koi Harmony with other games

	Koi Harmony Score 53This game	Koi Gate Score 75	Koi Kingdom Score 74	Koi Koi Score 72	Fortune Koi Score 64
Identity
Studio	Rarestone Gaming	Habanero	BF games	Slot Factory	EURASIAN Gaming
Released	6/24/2022	2/12/2017	4/6/2018	9/26/2023	9/24/2024
Math
RTP	96.47%	96.26%	98.08%	96.5%	—
Volatility	Low/Medium	Low volatility	Medium volatility	Medium/High	Low volatility
Max win	888×	—	—	3,750×	—
Format
Reels	1	5	5	5	5
Layout	1x3	5x3	5x3	5x3	5x3
Paylines	1	18	20	20	—
Min bet	0.1	0.18	0.2	0.2	0.1
Max bet	500	90	200	50	90
Features
Progressive	—	✓	—	—	—
Wild symbol	—	✓	✓	✓	✓
Free spins	—	✓	✓	✓	✓
Scatter symbol	—	✓	✓	✓	✓
Multiplier	—	✓	—	✓	✓
Bonus game	—	—	✓	—	—
Respins	✓	—	—	—	—

Every number is shown as a delta against Koi Harmony.

Comparing against

Koi Harmony

Rarestone Gaming

RTP

96.47%

Max win

888×

Score

+ Progressive+ Wild+ Free Spins+ Scatter+ Multiplier− Respins

+ Wild+ Free Spins+ Scatter+ Bonus Game− Respins

+ Wild+ Free Spins+ Scatter+ Multiplier− Respins

+ Wild+ Free Spins+ Scatter+ Multiplier− Respins

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