Forum:3 questions, Defender and Prime matreail dragon

2 questions i have about defender, the magical knight i belive the 1st Q is right 2nd Q wrong, 3rd about prime material dragon... idk

1st 2 Q, Lets say i have a magical citidal of endymion with plenty of spell counters on it

1) if i have a faceup Defender & my oppenant attacks a facedown spellcaster can i save it from being destroyed by battle?

2) if the only monster i have is a facedown defender can it save itself from being destroyed by battle, since its effect activates during damage step?

3) player 1 plays icarus attack to destroy player 2's only card (facedown trapcard) and one of his own facedown traps, can player 2 chain call of the haunted to revive prime material dragon and since its not being targeted/destroyed by icarus attack, it would instead destroy call of the haunted and it would destoyed prime dragon, so can player 2 use the dragons effect to nagate call of the haunted and protect the prime dragon or not?

sry if these questions are troublesome.