Take out inventory items/treasure chests

Your character retains the inventory items you brought in and the bag you used to bring them in.

If that character dies, any inventory items they brought with them will be lost. (This will be carried over if revived)

When you defeat the dungeon boss and return alive from the adventure, your inventory items and bag will be returned to your inventory and you will be able to use them again.

Repatriation

Some items and abilities allow you to send treasure chests, inventory items, bags, etc. you own to the surface.

The repatriated items will be available to you at the end of the adventure, even if you die.