many, if not most monsters cast shields from their opposite school to defend themselves because they are hurt more by that school.
a life monster casting a death shield is very common as it a storm monster casting a myth shield, etc.
Which part of my message didn't you understand?
Because of the very fact that they DID use a Death shield means that they are Life creatures. However, they are mislabeled in the game as being Storm. That is why I posted this message.