This is another one I would suggest leaving until you get the permanent Superflame, although your mileage may vary. The physics and hitboxes for this fight are very wonky. I flamed a bomb which was going straight down the middle (as was I) and it just went off to the northeast on a 45 degree angle for seemingly no reason at all. I similarly approached another straight bomb from a southeast 45 degree angle and it went straight back and hit him, so I think the physics are designed like that. Using the permanent Superflame negates the need for any caution at all as you just flame him to death from behind the ice with no risk at all to you.