How important do you think bringing the right types of foods/buffs/potions should be for challenging fights? *

For example in Runescape you can fight dragons. Even with the best armour and weapons in the game (Exluding dragon fire shields), you would struggle to kill a dragon because of how much damage dragon fire does. If you were prepared though you could bring a dragon fire potion that would add massive resistance to the dragon fire and make the fight possible (Yet still challenging depending on the type of dragon)