Sniff is Boney's only ability, of which allows him to sense the type and the weaknesses an the enemy. It does not work on some bosses, like the Forlorn Junk Heap that's encountered in the dumps of Thunder Tower in Chapter 5, the Masked Man in Chapter 7 or even New and Miracle Fassad of Chapters 7 and 8. It also does not work on the Putrid Moldyman in Chapter 8. It can be a valuable or worthless ability depending on what enemy you are facing.