First: a combo that is triggered by Din's Fire. It would use the next Combo in the line, much like the hammer does. Now, the second suggestion, that brings it all into focus:
Screen Flag: Trigger all combos-> Secret (and/or Item). A "triggerable" combo would be defined as any combo that can be altered by taking an action against it, such as hammer, lock block, slash (and its multiple variations), and the aforementioned Din's Fire. The reason for Din's Fire is for a puzzle like the opening to the Shadow Temple in OoT. (Stand in one spot, light all torches at once.)