From Brotato Wiki
Win a run with Glutton
Spicy Sauce is an in-game item that can be bought from Shop or can be found in a Crate. Most Items increase the Stats of the player while some of them provide unique effects.
Both the damage and the chance to cause an explosion increases when you gain additional Spicy Sauce Items. So the chance for an explosion is 25%/50%/75%/100% as you get up to 4 of the item. The damage is 50% of your Max HP and scales up to 200% of your Max HP when you have 4 of the item.