Should Fiery Decay being leveling Death Ray?

I have been using the Combo Fiery Decay a lot lately. I never use the 2 skills by themselves. My Fire Arrow is up to 45 now but my Death Ray is only up to 11. Should they both be getting gains from using Fiery Decay?

 

Fire Arrow is level 2, while Death Ray is level 3 - so there's that...

Are you CERTAIN that you have never used either of them alone ?
I mean, did you begin training both of them at the same level at the same time ?

 

I think I did have Fire Arrow first so I might have used it before I trained Death Ray. I guess I will just have to keep an eye on it. But both skills should be getting gains when using a combo correct?

 

That is correct, but I think you forgot that Death Ray was a level down, which makes it naturally slower to raise.
You are correct tho, both do raise when you use the combo.
You said it yourself, when you said you've never used them "alone". So for your Death Ray to have raised at all, it HAD to come from the combo.... right ?
I think you were wondering why there was such a disparity in their levels, but I think we've put that to bed - since the 3rd level skill will gain slower, all things being equal.

 

If you start as a mage you will also start with lvl 20 fire arrow.

 

Both skills do gain while using the combo.

 

This is true of any combo. Both skills gain levels.