HUD change, and its Mysteries

[Necrojon]

So with this new map we have not only new perks, guns, people, and game mechanics, we also have a beautiful new HUD to become accustomed to. We have nice new numbers, and an interesting image for what used to be the analog pad. But there are a few things that are also added to this, including what is in the following image.

(right click to view the full image)

In here we have what appears to be a new form of special grenade. It seems to be some form of flaming ball of some sort? Personally I think it has something to do with the demon dog that appears to be not only stationary but zombie eating.

Now in this image we have two things to try and understand, firstly we have the eye symbol right above the bullet count. I'm not 100% sure but I have a lot of faith in this being how the purgatory system works. We have a set limit as to how many times we can enter this mode, and we can replenish them by following the eye marker that appeared in the trailer at multiple spots.

Secondly we have what is in the top left corner, it appears to be a bundle of rope, or maybe a wire? I'm thinking this is a new way to tell us what the parts your carrying are. Instead of the small symbol in the bottom right as previously seen, I think this is just a nice improvement for the buildables system.

So what do you think? What does the new special grenade do? What do the eye symbols mean? And what could we be building with this wire, or rope bundle?