Item Stages Mod 1.12.2 is an add-on for the GameStages API. The new release allows you to set items and blocks into the custom progression systems.

How to use Item Stages
You’d better look up the GameStage API mod’s description to learn more about this addition.
Stages
They are parts of the progression that the mod pack or the server offers.
Players can open and experience them through a command. A questing mod, advancement or a Command Block will manage this item.
Setup
The creation utilizes CraftTweaker for configuration.
Others
The version supplements another ZenScript way to help you in adding stage restrictions.
It’s possible to deploy a specific item/block ID or an ore dictionary entry.
Effects
A message will take the place of the tooltip.
Equip the piece to offhand, armor, or bauble slot to cause it to drop
If it blocks something, a few stuff will begin to stop you from using it.
Keep a restricted object to make it drop instantly
The target will not appear in JEI.
You cannot right-click or left-click with the thing.
Item Stages is a CraftTweaker mod. It asks you to get and install Minecraft Forge so it can run.
How to install Item Stages Mod:
Assure that you have already installed Minecraft Forge
Define the location of the Minecraft application folder.
On the windows, open Run from the Start Menu, write %appdata% and click to Run
Open Mac on the finder, press and hold Alt and click to Library on the peak of the Menu Bar. Open the Application Support directory and look for Minecraft.
Put Item Stages Mod you have already downloaded (.jar) into Mods directory.
When you start using Minecraft, open the mod button, you will realize that Item Stages Mod has been set up.