Dark Spell - Cloud Shroud

I have an idea that I have seen mentioned in the past but not in this way.

A new Dark Spell called Shroud. It would hide attacking troops from defensive structures until they commence attack on it. This shroud will NOT prevent or reduce DMG imposed by bombs and traps and will also prevent the HEALER from healing any troops within it.
Specifications: Level 1 : 100 DE, Duration 8 seconds, Effect range circular 4 tiles.
NOTE: This CANNOT DEPLOY OR FUNCTION ON ANY PORTION OF THE OCCUPIED TERRITORY (White base border) If dropped on a hole in the middle of a base, it will only work in that hole and will not hide any attacking troop that has cast any damage or walked onto any base territory.

Attachment 168143

Each level increase will yield a 100 DE increase in cost, and increase the duration by 4 seconds.

THe spell will max at 4.
The level 2 research cost will be 60k DE, Level 3 is 85k DE, level 4 is 120k DE. The research time will follow that of Haste research times at the same levels.

The purpose:
This would change attack strategies to include specialized raids, and creatively deconstruct a base as well as allow for a different angle to build up a defense against the use of this spell. It's primary purpose would be to allow WB's an extra second to get to the walls. It would also allow for other troops to perform the same way.

Beware, once a troop attacks a structure, this will no longer hide that troop and all area damage attacks will function fully and damage surrounding units as normal. A troop will not be targeted until it has attacked a structure or exited the shroud or entered base territory.

The only troop that will be able to function in this shroud without being attacked is the healer. The healer can heal troops outside the shroud however the healer will not be able to heal any troop inside the shroud.