Dark spell: Necromancy

This is my idea:

This spell will be able to resurrect from tombstone all troops defeated in spell area.
All troops resurrected from necromancy have zombie/skeleton aspect and half life point and strenght of living troops. Heroes aren't affected by this spell (They aren't dead).
This dark spell only will work if a witch is on the field and his effects will disappeaer if a witch will be defeated.
Increasing level of this spell will increase radius of spell area.

I hope Supercell would consider my idea.
Sorry for my bad English.