Question(s) regarding "Enneacraft - Archa.Tail"
"After this card was flipped face-up, while it is in the monster zone, each time a monster(s) is sent to your opponent's GY, they take 900 damage."
Question number 1: is this a lingering effect that just happens when the requirement is met, or does Tail activate to inflict the damage (which would give my opponent the opportunity to do something)?
Question number 2: does the damage count per monster that is sent or just once per sent? For example if an XYZ Monster gets sent to the GY with 2 monsters as materials, does the 900 damage trigger once or three times?
Thanks in advance.