What items MUST I keep no matter what?

Salt Bag
Sahdina’s Memento

What else?

Nothing.

Dynamite.
Components.

Come on this was a serious question.

Obviously im not throwing away components…

And you’re getting serious answers. What exactly do you mean by must keep? Are you talking about items needed for quests (only the 2 you mentioned if you’re planning on doing the super secret quests and some dynamite for the Hidden Path, accessing the East March area and the 2nd secret quest), items you need for shrines (components/relics/other stuff), MIs that you may need to keep (no idea what classes you’re playing so can’t help with that), etc, etc. You get the idea.

I really like that shave butter by dollar shave club, you should keep that for sure.

For super secret quest 1:
-Stormheart.
-Salt Bag.

For super secret quest 2:
-Mythical Stormheart.
-Sahdina’s Memento.

That’s it!

It’s not necessary to hold on to it.

You must have the sword in the inventory when you take the other two items to the Bound Spirit. After that you can get rid of the sword, but it is necessary the first time for the quest.

Components, Dynamite, … and Scrap.

Save all unique items and then stop playing GD because you don’t want to add a stash mod. True story.

If you can assert self-control when using a stash manager life becomes so much easier. You can’t dissuade people from using one based on your own lack of it.