How to edit and customize Roblox backpack

I want to know how to edit the Roblox backpack like how they do it in Rogue Lineage.
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Are they re-creating a backpack system from scratch? or are they forking Roblox and just adding onto it?

I have tried forking but I couldnot find where. All I see was a Backpack module in the core gui on Roblox studio, but i dont know what calls it.
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Also, there is also a cool game that has the same concept but also does stuff with the inventory and not just the hotbar called Lost souls:


So I was wondering how they achieved this?

My guess is, they forked the script, set the coreguiEnabled property of the original backpack to false, edited their script to fit their purposes, and went from there.

  1. ayo shinobi dragon knight???
  2. what is that game link
  3. i would like to know too

They probably made their own backpack.

Currently looking into this subject myself, and I want to mention that it’s unlikely considering how genuinely annoying making a custom backpack manager is.