During your Main Phase: You can reveal 1 LIGHT Fairy monster in your hand, and if you do, add 1 Level 7 LIGHT Dragon monster from your Deck to your hand, then place that revealed monster on the bottom of your Deck.
If your opponent activates a card or effect: You can Special Summon 1 Level 7 LIGHT Dragon monster from your hand.
You can only use 1 "Starry Knight Ceremony" effect per turn, and only once that turn.