What essential items should you stock up on in the event of a world crisis ?

Water, fuel in case of power outages for an alternative way to cook and heat water, batteries, medicine, first aid supplies, health & hygiene items, various foods. If you have an excess of alcohol or other things in demand you could use those to barter with. Protein foods, easy to heat or cook items, shelf stable dairy ( calcium tablets in case of shortages ), flours and other pantry foods to make breads etc with and paper copies of simple recipes to make them.