woomyDX: Video game competitive rank predictor [2020]

A Windows app that reverse-engineers the Nintendo Switch Online app to predict competitive ranking points in real time

1. Project Overview

What is woomyDX?

woomyDX is a Windows application for Splatoon 2 players in the X Rank competitive tier. It predicts match outcome impacts on ranking points in real time and simplifies technical setup steps. Using a Man-In-The-Middle (MITM) technique, it intercepts network traffic from the Nintendo Switch Online app to provide players with hidden matchmaking insights – specifically showing how wins/losses would affect their rankings.

Project Goals

  • Show players immediate feedback on how match outcomes would change their X Rank points
  • Automate complicated Android ROM/proxy configurations for non-technical users
  • Deliver clear in-app displays and text-file outputs compatible with streaming software

Technologies: C++/MFC, Android Networking, OAuth, Reverse Engineering

Source: snowpoke/XPowerControl

2. Technologies and Implementation Details

Key Technologies

  • C++ & MFC: Core Windows app built with Microsoft’s GUI framework
  • Boost Libraries: Provides filesystem tools, string operations, and time/date handling
  • Windows API: Manages OS-level tasks like registry access and processes
  • MITM Proxy: Intercepts Nintendo Switch Online app traffic
  • BlueStacks + Custom ROM: Android emulator environment for executing MITM attacks

Implementation Details

  • Automated Setup: Checks for required software, installs missing dependencies (Android emulator, proxy tools), and configures network settings automatically.
  • MITM Execution: Launches a proxy server and modified Android environment to capture authentication tokens from the Nintendo Switch Online app.
  • Data Pipeline: Pulls SplatNet 2 match data via authenticated API calls and processes JSON responses.
  • Rank Prediction: Uses a custom algorithm to calculate X Rank point changes based on match conditions.

3. Impact & Future Plans

Impact and Outcome

  • Delivered real-time rank insights to users during Splatoon 2’s peak
  • Made advanced tracking tools accessible to casual players via streamlined setup
  • Demonstrated the value of game data extraction for competitive insights and streaming integrations
  • Operated as an affordable fan service during the game’s lifecycle

Roadmap

  • (Development concluded following Splatoon 3’s release.)

4. Why This Matters

woomyDX gave Splatoon 2 players unprecedented transparency into X Rank progression. By automating technical hurdles and providing live feedback, it improved competitive decision-making and showcased skills in:

  • Reverse Engineering: Working with unofficial APIs
  • Data Utilization: Creating predictive ranking algorithms
  • Windows Development: Building GUI apps, system integrations, and streaming-compatible outputs