I think he's getting at:
Scarifice a Photon
or Ray of Light, Cast Holy Light.
or something like that. This clarifies it works on either not both (both being you need to kill one of each).
I like the card just has a spam quality that I think will turn it towards OP.
Generation:
A great concept and definately useful for Light but now with Hope in play it would become completly OP in a few turns. (imagine 6 of these flown with a Hope shield, you would reduce damage by at least 6 every turn becoming invincible very fast)
Maybe it generates 2 Photons for 1

or something like that to make it activable rather than automatic.
Thanks for your great work keep it up.
Scyther