When I saw the "light" challenge, I immediately thought about stamping on candles.

The brads on the tree were just pushed in the wax, I used hot glue on the star and ribbons. I found out that's the only thing that would hold good on candles - even the strongest glue dots don't do the job properly.
Challenges:
C.R.A.F.T. - Christmas gift
Crafty cardmakers - heat embossing
The Ribbon Girls - Christmas + ribbon
Just Some Lines - Handmade gift