I can't think of a better name for this idea that just popped into my head except Saboteur, unfortunately.

While I'm held captive at an outpost, reduce its sonar range by X%. (would 50% be too extreme?) I can't be released. (except remotely, by my controller? maybe?)
Plus, hence the title, when you hire this Specialist you should probably get two or three of them.

While reading this thread I learned about the Illusionist, and my mind went spinning off in the direction of fogplay. I've also been playing a game with a Navigator and having a blast not having to worry about stumbling into an ambush and losing my specialists.

With that in mind, it'd be fun to have a specialist whose role is to be thrown away and lost. Also, depending on whether or not the owner can release their own specialist from another player's outpost, it could make for a weird diplomatic situation not unlike -- but uniquely different from -- two allies accidentally attacking the same outpost.

alternatively, in the same vein:

Each outpost containing one or more captive specialists of yours has its sonar range reduced by X%.

but I like my first proposal better! It's like an aggressive (rather than defensive) Saboteur!

I'm only in the middle of my second game of Subterfuge, so... I'd be really interested to hear from more experienced players how they feel about my little idea! Useless? A terror to play against? Boring? Too weird? ...???

hm. i like this!

It sounds interesting.

You'd have to find a decent counter though since someone could just send that specialist off to any outpost and have it be captured...

Can't travel alone maybe?

Maybe the hypnotist can convert him, but there is no other way to get rid of it?

Assassins work too. Amusingly, so do saboteurs... kind of?

Assassins and saboteurs could deflect an attack but couldn't cure an infected outpost.

A saboteur couldn't but an assassin could. Someone ELSE'S assassin, so that combat would take place.