While this card is face-up on the field, all monsters on the field and in either player's Graveyard are treated as DARK monsters
Personally though, I used the in-game shops for cards as an immersion thing
If the effect has been triggered at [When Digivolving] and activated, it can not be activated again on the same turn, even if it's triggered [When Attacking]
Especially since they'll often be summoned on the opponent's turn, making them vulnerable to being destroyed by battle
Se lo fai, i mostri che controlli non possono essere distrutti in battaglia , e tu non subisci danno da combattimento in questo turno
This amount of burn damage wont win duels on its own, but in a deck primarily set up around helping your Monsters during the Battle Phase, this effect can help you reduce your opponents life points fast