# Nucleus Co-op Wiki: Complete Site Guide

> Nucleus Co-op Wiki is an independent English resource for Windows users who need a verified Nucleus Co-op download, a game-specific handler workflow, controller separation, supported-game notes, and practical troubleshooting. It does not present itself as the official Nucleus Co-op project and does not distribute cracked games or unauthorized copies.

## Site Background

The site exists because Nucleus Co-op searches often combine several different questions: where to download the Windows application, how the installer differs from the portable ZIP, how handlers work, whether a particular PC game can launch multiple instances, whether controllers stay separate, whether Wi-Fi or online services are required, and how to recover from OneDrive, access-denied, ProtoInput, resolution, or handler errors. The editorial approach is to separate those layers and state compatibility limits instead of claiming that every title works the same way.

The release page records source provenance and checked file facts separately from local security decisions. The guide uses official or clearly identified external links for release, documentation, and handler references where they improve verification. Visitors remain responsible for legitimate game ownership, backups, security scans, game licenses, and the exact behavior of third-party providers. Corrections and page-specific technical feedback can be sent to support@nucleuscoop.wiki.

## Content Category Details

### [Download and first installation](https://nucleuscoop.wiki/download/)

The download page presents the checked v2.4.1 Installer.exe and NucleusApp.zip release assets, explains the difference between guided installation and portable extraction, lists prerequisites, and links to the official release source. The installation guide then turns the download into a controlled first launch: use a local writable folder, open the application once, select one game handler, assign a simple input path, and test a short session.

### [How the application and handlers work](https://nucleuscoop.wiki/how-it-works/)

These pages explain that Nucleus Co-op coordinates supported game instances, windows, and local inputs, while the handler supplies game-specific paths, launch arguments, isolation rules, and workarounds. The game still controls its own gameplay, save system, LAN or online behavior, and multiplayer limits. The handler guide covers the built-in downloader, manual handler boundaries, WebView2-related symptoms, version changes, and source hygiene.

### [Games and game-specific setup](https://nucleuscoop.wiki/games/)

The searchable games directory is the main entry point for long-tail game intent. Implemented detail pages cover Risk of Rain 2, Call of Duty: Black Ops II, Minecraft Java, Palworld, Elden Ring Nightreign, Vampire Survivors, Devil May Cry 5, and Core Keeper. Each page focuses on exact edition and build matching, handler notes, controller testing, window layout, connection behavior, save backups, and cautious troubleshooting. The entries are handler-dependent, not permanent compatibility guarantees.

### [Elden Ring Nightreign Nucleus Co-op setup](https://nucleuscoop.wiki/games/elden-ring-nightreign/)

### [Vampire Survivors Nucleus Co-op setup](https://nucleuscoop.wiki/games/vampire-survivors/)

This page covers the Vampire Survivors-specific Nucleus Co-op workflow: verify the current handler, start the legitimate Windows game normally, separate controller input, test a short co-op session, and protect saves before changing versions or connection settings.

The Nightreign guide is a game-specific workflow for checking the current handler, matching the installed game build, testing separate inputs and windows, separating connection from save behavior, and investigating Deep of Night save issues with backups. It explicitly distinguishes Nightreign from base Elden Ring and does not promise online support or shared saves.

### [Devil May Cry 5 Nucleus Co-op split-screen setup](https://nucleuscoop.wiki/games/devil-may-cry-5/)

The DMC5 guide explains that PC local split screen is not a native game menu and that any Nucleus Co-op attempt depends on a compatible community trainer, handler, exact game build, and separate input devices. It uses official Steam game media for context, but does not present those images as proof of Nucleus compatibility. The workflow starts with a clean launch, checks trainer and handler sources, tests two windows and independent input, separates local multi-instance behavior from online play, and records a rollback point before a longer session.

### [Core Keeper Nucleus Co-op setup](https://nucleuscoop.wiki/games/core-keeper/)

The Core Keeper guide separates the game's own multiplayer and world-joining behavior from Nucleus Co-op process coordination. It checks the current handler and installed build, starts with a normal game launch, tests two windows and independent input, protects worlds and player data, and records the host/join step and changed save folders. Official Steam context media and editorial diagrams are labeled as context or illustrations, not proof of compatibility. The page avoids a permanent support promise because handler notes and game builds can change.

### [Controllers, online use, and troubleshooting](https://nucleuscoop.wiki/controllers/)

The controller guide covers XInput, DirectInput, PS4, PS5, Joy-Con, keyboard, mouse, device order, focus, and the symptom where one controller controls both instances. The online guide separates offline launch, handler downloads, Wi-Fi, LAN discovery, online services, mods, and firewall rules. The troubleshooting hub organizes observed symptoms into permission, path, handler, input, display, and network checks.

### [Safety and FAQ resources](https://nucleuscoop.wiki/is-nucleus-coop-safe/)

The safety page uses a source-first checklist for official release assets, file names, versions, formats, antivirus warnings, and the boundary between the application, handlers, mods, and legitimate game files. The FAQ condenses the highest-intent questions about downloads, installation, controllers, games, online play, Wi-Fi, saves, uninstalling, safety, and firewall access.

## User Value

The site helps visitors make a sequence of concrete decisions: choose the correct application asset, avoid a stale or random mirror, keep the program outside a cloud-synced path, match a handler to the exact game edition and build, verify that each controller reaches only the intended window, distinguish an offline app symptom from a game networking limitation, and protect saves before changing instance files. It also helps a visitor report a failure with useful evidence: application version, game build, handler version, install path, input devices, launch stage, connection mode, and exact error message.

## Latest Update Content

### [August 2026 English site launch](https://nucleuscoop.wiki/)

In August 2026, the site received an English-first information architecture with direct download access, installation and handler guides, a searchable games directory, eight game-specific pages, controller and online explainers, safety guidance, a detailed FAQ, updated legal pages, and AI-readable site context files.

### [August 2026 release facts](https://nucleuscoop.wiki/download/)

The download guide records v2.4.1 as the checked release used by this implementation, with separate Installer.exe and NucleusApp.zip assets, prerequisite notes, a 15-second in-page download status, and links to the official SplitScreen-Me GitHub release source. Release facts should be reviewed again whenever the official project publishes a newer tag.