PRADEEP HEBBALLI

Posted on May 19

OpenOdds Casino

#builtwithmedo #gamedev

OpenOdds Casino: A Transparent Casino-Style Simulator Where the Odds Are Visible

I built OpenOdds Casino for the MeDo Hackathon.

Most casino-style apps are built around suspense, colors, music, and excitement. But one important thing is usually hidden from the user:

the real odds.

OpenOdds Casino was built around a different idea:

What if a casino-style game showed the win probability, loss probability, payout, house edge, and audit trail before every play?

That is the core concept behind OpenOdds Casino.

What Is OpenOdds Casino?

OpenOdds Casino is a virtual-credit-only casino-style simulator built with MeDo.

It is not a real-money gambling platform.

There are:

No deposits
No withdrawals
No wallet
No crypto
No redeemable prizes
No real-money rewards

Every user starts with 1,000 virtual demo credits, and all games are played only inside the simulation.

The goal is to demonstrate how casino-style digital experiences can be made more transparent, auditable, and responsible.

The Main Idea

Most games focus on the experience first and the math second.

OpenOdds Casino puts the math directly in front of the user.

Before playing any game, the user can see:

Win probability
Loss probability
Payout multiplier
Expected return
House edge
Risk level
Game explanation
Audit logic

The maximum win probability for any game is capped at 20%, and this is clearly displayed.

The app does not hide the odds. It makes the odds part of the experience.

Games Included

Game	Win Probability	Loss Probability	Payout	House Edge
Neon Slots	12%	88%	5x	40%
Lucky Wheel	15%	85%	4x	40%
Dice Duel	18%	82%	3x	46%
Card Flip	20%	80%	2.5x	50%
Crash Line	10%	90%	6x	40%
Treasure Vault	8%	92%	8x	36%
Roulette Lite	16%	84%	4x	36%
Coin Storm	14%	86%	5x	30%

Each game is intentionally transparent about the fact that the odds are unfavorable to the player.

How the Math Works

The app uses a simple transparent probability model.

For each game round:

randomValue = random number between 0 and 1

if randomValue <= gameWinProbability:
    result = win
else:
    result = loss

The expected return is calculated as:

$$
Expected\ Return = Win\ Probability \times Payout\ Multiplier
$$

The house edge is calculated as:

$$
House\ Edge = (1 - Expected\ Return) \times 100
$$

For example, Neon Slots has a win probability of 12% and a payout of 5x.

$$
Expected\ Return = 0.12 \times 5 = 0.60
$$

$$
House\ Edge = (1 - 0.60) \times 100 = 40\%
$$

This means the game is mathematically unfavorable, but the user sees that clearly before playing.

That is the point of OpenOdds Casino.

Transparent Logic Example

{
  "game": "Neon Slots",
  "winProbability": 0.12,
  "lossProbability": 0.88,
  "payoutMultiplier": 5,
  "expectedReturn": 0.60,
  "houseEdge": "40%",
  "logic": "If randomValue <= 0.12, user wins. Otherwise, user loses."
}

Transparency Engine

The Transparency Engine is the core trust layer of the app.

It shows:

All game probabilities
Loss probabilities
Payout multipliers
Expected return
House edge
Risk level
Probability formula

Instead of hiding the odds behind the visual experience, the app makes the odds part of the experience.

Open Analysis Page

The Open Analysis page explains how the simulator works.

It includes:

JSON-style game configuration
Probability settings
Payout multipliers
House-edge values
Pseudo-code for outcome generation
Audit-log schema
Local-storage schema
Virtual credit logic

This page was added because transparency should not only be visual. It should also be structural.

Audit Log

Every play is recorded locally in an audit log.

Each audit entry includes:

Timestamp
Game name
Bet amount
Win probability
Loss probability
Result
Credits before play
Credits after play
Payout amount
Play ID
Probability rule used

The user can also export the audit log as a CSV file.

This makes the app more trustworthy because every round is traceable.

Responsible Play Features

OpenOdds Casino includes responsible-play safeguards because casino-style interaction can become harmful if it is designed irresponsibly.

The app includes:

[x] Virtual credits only
[x] Clear no-real-money disclaimer
[x] No deposits or withdrawals
[x] No redeemable rewards
[x] No fake jackpot language
[x] No near-miss manipulation
[x] No countdown pressure
[x] No urgency mechanics
[x] Break reminders
[x] Loss warnings
[x] Reduced Stimulation Mode
[x] Optional audio controls

Responsible Play is not hidden in fine print. It is a dedicated part of the app.

Audio and Reduced Stimulation Mode

The app includes casino-style music and sound effects, but audio is controlled carefully.

Audio is:

Muted by default
Started only after user interaction
Optional
Controlled through music and SFX toggles
Adjustable through a volume slider
Disabled through Mute All

Reduced Stimulation Mode disables:

Music
Confetti
Flashing effects
Intense animations
High-energy sound effects

The app remains fully usable without audio.

How I Built It With MeDo

I built OpenOdds Casino using MeDo by creating a detailed requirement-driven prompt and refining it through multiple testing passes.

The app was structured around four layers:

Game Layer

Handles virtual-credit gameplay, bet selection, win/loss results, payout calculation, and animations.
Transparency Layer

Displays probabilities, payout multipliers, expected return, house edge, and risk levels.
Audit Layer

Records every play locally and supports CSV export.
Responsible Play Layer

Provides disclaimers, warnings, reduced stimulation controls, and safe interaction rules.

MeDo helped turn this concept into a polished, interactive prototype with a strong visual identity.

Challenges Faced

The main challenge was balancing three things:

Making the app vibrant and engaging
Keeping the odds fully transparent
Avoiding real-money gambling functionality

Casino-style interfaces can easily become manipulative if they use fake urgency, jackpot language, near-miss effects, or unclear rewards.

So the design had to stay exciting without becoming misleading.

Another challenge was testing functional details like:

Reset credits
Audio controls
Local storage
Audit log updates
CSV export
Probability consistency
Mobile responsiveness
Responsible-play warnings

The app needed to look polished, but also behave correctly.

What I Learned

This project taught me that transparency can be a product feature.

A casino-style app does not have to hide the math. It can show users exactly what they are interacting with.

I also learned that serious app-building requires:

Clear requirements
Testable logic
Strong state handling
Purpose-aware QA
Edge-case testing
Responsible design boundaries
Honest user communication

The biggest lesson was simple:

A beautiful app is not enough. The logic must be visible, testable, and trustworthy.

Why This Project Matters

OpenOdds Casino is not trying to become a gambling platform.

It is a prototype showing how transparency, auditability, and responsible-play design can be built into casino-style digital experiences.

It demonstrates a future direction where users are not just entertained, but also informed.

In short:

OpenOdds Casino turns hidden odds into visible information.

Built With

MeDo
Virtual-credit game logic
Local storage
CSV export
Probability modeling
Transparent house-edge calculations
Responsible-play safeguards
Audio controls
Responsive UI design

Try the App

Try OpenOdds Casino here:

https://app-bqlx7z4f394x.appmedo.com/

Final Thought

OpenOdds Casino is a premium casino-style simulator with one core difference:

the odds are not hidden.

Every game shows the probability, the risk, the payout, and the house edge before the user plays.

That makes it more than a game demo.

It is a transparency-first experiment in responsible digital entertainment.

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