Noob Prophs Question

i feel pretty dumb asking this but i read somewhere that there are really only four missions that one HAS to do to beat prophs. what are they? i assume the infusion and the last one are givens but the other two? sorry for noob question, but i've only just played through all of the missions but i'm taking a character over from NF and don't want to do all of them again. thanks in advance.

Thunderhead Keep which you have to do to get to the Fire Islands and the 3 missions on the Fire Islands which lead into each other(Ring of Fire brings you to Abaddon's Mouth, Abaddon's Mouth brings you to Hell's Precipice and Hell's being the last mission).

Dark Flame is correct. You dont really HAVE to get infused, but it is a good idea. Also you could also consider the primary quest that you receive at Ember Light Camp (where you kill the group of White Mantle bosses ..forgot the name) as a must do, since you cant get to the Ring of Fire mission without it.

While infusion is a good idea, you don't need to do Iron Mines of Moladune to get infused. Infusion is also available in the mineral springs, ring of fire and abbadon's mouth too.