That is Rebirth Fire. The fire which purifies the evil and heals wounds.
[AUTO](VC):[Choose a card from your damage zone, and put it into the bottom of your deck] At the beginning of your main phase, you may pay the cost. If you do, put the top card of your deck into your damage zone. If an «Angel Feather» is put into your damage zone this way, this unit gets [Power]+3000 until end of turn, and if it is not, [Rest] this unit.