I've been experimenting with a custom mod pack.  So far I've had minimal issues with crashes and can usually parse them out from the crash report but for the last two days I've been fighting with this and getting nowhere. 

I'm using Curseforge and the launcher opens, there's a flash of the Minecraft window, then I get a crash report with an exit code of -1.   

I get this -

The game crashed whilst initializing game Error: java.lang.RuntimeException: null

And here's the crash report - https://hastebin.com/share/ocojobivik.perl

 

Thanks for any help.

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