It took me three attempts (Yes, I'm save-scumming, but that's how I choose to play the game). It took me three attempt not because the goatfolks were so hard. I've killed them in small groups before. The problem was the shaman guy.
There are two downstairs entrances to this place. On my first attempt to scout out what happens, I go down the northern stairs, which is where I first spotted the goatfolk group and they are decently close to the stairs.
You are stunned for this round!
You are stunned for this round!
You are stunned for this round!
His stuns do anywhere from no damage to a whopping 17, and for me they lasted up to three turns. Oh, and I'm not really stunned. I run in terror TOWARDS THEM. So instead of being on the safety of the stairs, I'm now surrounded by them. I have 85 max hp (Miraculously on this playthrough I've not had to savescum except once when I mashed down the movement key and watched as the program lagged to keep up. When it stopped I was dead due to 3 salthoppers), and I'm pretty high level. I had around 50 hp by the end of that, and 20-30 by the time I make it back to the stairs fleeing. A goatfolk followed me up and I killed it. I waited for others, none came, so I just meditated and regenned my health. That happened a couple more times in the same fashion with me whittling down their health. The last time it happened I somehow ended up with a few goatfolk between me and the stairs but there was a goatfolk that just
stayed on the stairs. Before I could kill him I was blasted again with the terror-stun and died.
So I save-scum and decide to create some grenades in order to take them down. I hop down, getting terror-stunned, but this time I end up like this:
With the stairs to the Northwest. I never got the opportunity to lob the grenade.
The third time I used the other set of stairs, made more grenades, and equipped my sniper rifle. It wasn't far from them, but as soon as I saw the shaman I was hit with the terror-stun. Luckily my guy ran into a small hallway (the one leading back to where I came). I decide to guard the hallway, forcing them into a chokepoint. I kill the first two goatfolks, get terror-stunned and run further back. With my life teetering at 20 hp, I fight off the rest of the goatfolk (The sowers didn't firebomb me, luckily), and end up near 10 hp with the last terror-stun which hits me from behind a wall because I'm not running the new version. I try to beat the terror-stun with my regen, but it kept knocking me down until I used meditate and then regenned. I got my health to about 50 then rushed the shaman. I killed him in two hits, got his stuff, and finished another area.
Of note, Goatfolk hornblowers are similar terror-inducers, but I don't think they deal nearly as much damage.
tl;dr: Unless you save-scum or have hp upwards of 60 (upwards of 120 in the case of the group I met) HP, do
NOT mess with purple Goatfolk Shamans, even if they have floating shinies that you covet.