This is a modified Night Hound ultimate. It is a normal skill now, taking ability spot 3. It has increased fade time and a proximity stealth instead of full stealth.
<?xml version="1.0" encoding="UTF-8"?>
<startfade a="source_attackduration" />
<startfade a="castduration" />
Now the problem is with the proxistealth. I built this together using Night Hound ult and Scout ward as reference. The problem is that even when you are faded into the invis state heroes can still autoattack you. Example:
The custom hero is standind still with hold position, the proxistealth radius is 300 meaning everything past 300 can't see him. Now arachna walks nearby using attack-move and when she comes into attack range she will start to attack the custom hero from a 600 distance. In other words she is shooting air and none of the attacks hit the target, it's just miss, miss, miss.
Even if you idle with a hero it will aggro to the custom hero if he comes into aggro range.
So what gives?
Basically the skill would be like Night Hounds ultimate except if you go close enough to him you will see him even without wards, dust or anything of the sort, like you can see electric eyes.