Ghost Portal was a long time datamined skin and was originally thought to be paired with the Cloak Star skin. It turns out that it's part of the Skull Trooper Challenges and can be only obtained if you have the Skull Trooper skin and you complete those challenges.
It also has new styles, there's the original, green, and purple. The purple version, however, is limited to players who originally purchase the Skull Trooper during its first release.
Official Description
I just got a chill.
Cosmetic Information
- Rarity: Epic
- Type: Back Bling
- Availability: Skin
Ghost Portal's Attachments
Attachments are items that come with a cosmetic when a particular one is purchased.
Ghost Portal Images
Skull Squad Set
The first thing I thought when I saw this is, “This would go great with the Skull Trooper.” Anyone else think that?
Yeah. I think that it will be for a Halloween event; like the Birthday Cake or something…
I think it might be part of a Halloween event
I think it will be part of season 6
Maybe you’ll get this via Halloween challenges?
Nah, I don’t think. It doesn’t look like the other back blings that are gives for free.
You never know ¯\_(ツ)_/¯