Unfortunately, in order to play you will need to host the files through a web server. The easiest way is to create a new file in the same directory as the one that you extracted the zip to. You can call it "game.ps1". Paste the contents:

Install-Module WebServer
Import-Module WebServer
# Already running? Restart the web server
if (Get-Job -Name "WebServer" -ErrorAction SilentlyContinue) {
    Stop-Job -Name "WebServer"
    Remove-Job -Name "WebServer"
}
# Start the game
Start-Job -Name "WebServer" { Start-Webserver }
# Open the browser
. 'C:\Program Files (x86)\Microsoft\Edge\Application\msedge.exe' "http://localhost:8080"

Then save the file, then right click the file, and then select "Show more options" then "Run with PowerShell"

Is the "Run with PowerShell option missing from the menu? Read on

In Windows 11, at the top of your explorer window, click "...", then "options". Inside the Folder Options menu, click the View tab. Then untick the "Hide extensions for known file types" and apply. Now you probably see that the file was actually named "game.ps1.txt" or similar. Now you can edit the entire name of the file to "game.ps1". Confirm the change. Right click the file, show more options, then Run with PowerShell

In Windows 10, at the top of your explorer window, click View, then tick the "File name extensions" box. Now you can edit the name of the file to "game.ps1", then right click and Run with PowerShell

Doesnt work in any of my explorers.