Forum:Dark Resonator

i got a Dark Resonator in facedown and is attacked, does its effect activate? if that is so, after the first attack dark resonator survives, and is attacked again, if i chained book of moon to it, will its effect reset and survive again or will it be destroyed?

does Krebons need to be face up so it can negate attack or will it can be face down and after being flipped due to attack, can i use its effect to negate the attack or will it be destroyed?