What Hidden Abilities are available?

Under the Hood

So, since I'm a capable programmer with nothing better to do, I took a break from playing XCOM2 to dive into XCOM ModBuddy. All of the following is taken directly from the SDK. Presume all statements to refer only to the base game, unless otherwise qualified.

All potential Hidden Abilities come from soldier classes, which, in the base game, means Ranger, Grenadier, Sharpshooter, Specialist, or Psi Operative. What the game does is iterate through all the classes, checking each class' ability list for abilities that are marked "CrossClassEligible". Abilities from the current unit's class aren't added as possibilities. (So a Sharpshooter will never get "Death from Above" as a Hidden Ability, even though Hidden Ability is Cross-Class eligible)

It looks like there are hooks for an extra list of non class-associated abilities, and I've heard people get "Lightning Reflexes", which isn't a class perk, but I haven't found that list yet.

After assembling this list, the game simply generates a random number from 1 - X (where X is the total number of skills) and assigns that as the Soldier's Hidden Ability.

TLDR: Most abilities are class-specific, and you will never get abilities from your class as Hidden Abilities.

List of Cross-Class Skills

Grenadier

Hail of Bullets
Blast Padding
Holo Targeting
Shredder
Volatile Mix
Chain Shot
Rupture
Salvo

Ranger

Run & Gun
Untouchable
Implacable
Shadowstep
Phantom
Deep Cover
Rapid Fire

Sharpshooter

Deadeye
Death From Above
Serial
Kill Zone
Aim

Specialist

Ever Vigilant
Guardian
Covering Fire

Advanced Warfare Center (Unique)

Lightning Reflexes

(Think the Specialist misses out since most of their skills are Gremlin Focused)