O
I didn't know that either
And yeah, Caps, green would be healing. It's what Klippy used for healing in the first game, and what it shows up as in the actual TDD game, so I would say it's a rather safe bet.
And also, Caps, you could probably look up the classes and terrors from TDD and guess at what they do based on what they do in the game. It certainly won't be exact, but it might give you an idea. The skills won't be the exact same, but they'll probably be similar. That's why I guessed that the +15 stress heal was from the Jester, as his Inspiring Tune skill in the game heals about that much stress, though in the game it also comes with a buff that grants stress resistance, and that may not be present here.
edit: not sure if the ghoul would have done much damage, but in the first game, the only dangerously high attack I recall was the giant's, and that was a day attack. The ghoul is a more dangerous terror, but in my experiences, he does more stress damage than actual damage. Might not be the case here, though.
As for the Siren, I'm not sure if she'd retaliate. She does get protection from the fish people, though, as she's their queen (kind of?) and there is one that she summons that can guard her. Probably not the case here, but it could be a possibility. (The only actual counters in the real game, however, are when the Highwayman or Man-at-Arms activate Riposte)