You and the rest of the townsfolk are stranded in Tresna with nothing. Your shop is the way out, for you and eventually for everyone.

Greed is the difficulty setting

Fill the backpack and get out. Going deeper means better relics and a much better chance of losing everything you are carrying, and knowing when to turn round is the actual skill.

Running a shop is a game too

Back home you price the loot, lay out the shop floor, haggle and deal with whatever the day throws at you. Junk sells as well as treasure if you understand your customers.

Invest in the village

Money you make goes back into your neighbours' businesses, which unlocks better weapons, armour and upgrades. A busier Tresna brings more people past your door, which brings in more money.