Question about Lucky and Blood Vengeance

[konming]

Concerning the unit attribute lucky, I wonder if it only works against physical attack (melee and arrow). Does it work against spells? Like fireball, wrathful sky etc. Also does it save the unit 50% of time against instant kill spell like soul slay or charm? What about spells that produce stun or paralyzation damages?

The same question can be asked about Blood vengeance as well. I know blood vengence may reflect physical and even spell damage, but what about AOE spell damage or battlefield spell damage? How about status change like paralyze?