Hill Trolls: sources?

[Corvo]

Yesterday occurred to me that I don't remember where are "Hill Trolls" mentioned in Tolkien's writings.

I don't have the books at hand, but going from memory TOR's Hill Trolls looks like the "Gorgoroth Trolls" mentioned in the Battle of Morannon.
And/or are they the Olog-hai mentioned in tLotR appendix?
Can these Trolls endure sunlight? Or were Sauron's dark clouds that let them fight during the day?

I'm asking because I remember distinctly that Aragorn gently scolded Pippin for forgetting that Trolls cannot endure the sunlight (Pippin saw Bilbo's 3 stone Trolls and panicked): from his behaviour I got the impression that no troll can endure full sunlight...

[Hermes Serpent]

The rules are a bit ambivalent about this. I remember seeing that Stone Trolls are singled out as being vulnerable to the Sun but most of the other write-ups give no indication one way or the other.

"Nobody knows if Cave-Trolls can endure the light of the
sun, as they never leave their hunting grounds under
mountains, hills and fells." LMB p78
"A very ancient breed, Stone-Trolls owe their name to the fact that they
turn to stone if exposed to the light of the Sun." LMB p81

Nothing specific for Hill or Mountain Trolls. Although a comment in Heart implies that Hill Trolls avoid the Sun p49
Snow Trolls - "When the wind blows and snow
reduces the visibility to mere inches, they go out to hunt in
great numbers. " implying that they avoid the Sun.

The Trolls in the Trollshaws (Rivendell p36) "hide from the daylight in caves under high cliffs." but there is no specific breed of troll mentioned. Under the entry for Ettins it mentions "Every traveller knows that Stone-Trolls turn to stone if exposed to the light of the sun." Again singling out just Stone Trolls.

[PST]

And it happened that when Arathorn and Gilraen had been married only one year, Arador was taken by hill-trolls in the Coldfells north of Rivendell and was slain.

But through them there came striding up, roaring like beasts, a great company of hill-trolls out of Gorgoroth. Taller and broader than Men they were, and they were clad only in close-fitting mesh of horny scales, or maybe that was their hideous hide; but they bore round bucklers huge and black and wielded heavy hammers in their knotted hands.

[Otaku-sempai]

The only Trolls that I know for certain could endure the light of the Sun were the Olog-hai. However, they were so unlike other Trolls that they were often mistaken for huge Orcs. From LotR, Appendix F:

But at the end of the Third Age a troll-race not before seen appeared in southern Mirkwood and in the mountain borders of Mordor. Olog-hai they were called in the Black Speech. That Sauron bred them none doubted, though from what stock was not known. Some held that they were not Trolls but giant Orcs; but the Olog-hai were in fashion of body and mind quite unlike even the largest of Orc-kind, whom they far surpassed in size and power. Trolls they were, but filled with the evil will of their master; a fell race, strong, agile, fierce and cunning, but harder than stone. Unlike the older race of the Twilight they could endure the Sun, so long as the will of Sauron held sway upon them. They spoke little, and the only tongue that they knew was the Black Speech of Barad-dûr.

According to some sources, Snow-trolls would become pillars of ice and slag under the Sun instead of just turning to stone. On the other hand, that might be a reference from Tolkien's Christmas Letters and might not properly apply to Middle-earth Trolls.

[poosticks7]

Well I go with the idea that there are Hill Trolls as a distinct breed but that the Olog-Hai are a special breed of Hill Troll that the big S as tampered with to help them endure the sun better (and make them more intelligent).

That's why I added the Olog-Hai as baddies in Rich H's additional rules - they are super hill trolls - rare but deadly.

[Corvo]

Well, thank you all for the feedback. And welcome on board, PST
Apparently the question on Hill Trolls and Sun is left deliberately vague.

I'm thinking that in my campaign only Stone Trolls will turn into stone if touched by the Sun, but even the other ones will avoid and fear it (even more than the Orcs)

[Otaku-sempai]

I'm thinking that in my campaign only Stone Trolls will turn into stone if touched by the Sun, but even the other ones will avoid and fear it (even more than the Orcs)

Based on Tolkien's own words, I would conclude that all Trolls except for the Olog-hai risk turning to stone under the light of the Sun. However, order your own game as you think best!

[Corvo]

I'm thinking that in my campaign only Stone Trolls will turn into stone if touched by the Sun, but even the other ones will avoid and fear it (even more than the Orcs)

Based on Tolkien's own words, I would conclude that all Trolls except for the Olog-hai risk turning to stone under the light of the Sun. However, order your own game as you think best!

I largely agree. And I'm shifting toward "turn to stone" positions.

Now, for conversation's sake, I can say that my "problem" is that we don't know if the Hill Trolls are the Olog-hai. Or which trolls can be defined as Olog-hai.

We can speculate that, by TOR canon, people don't think to Cave Trolls as Olog-hai, because "Nobody knows if Cave-Trolls can endure the light of the sun".
By the same phrase, we can suppose that people is aware that at least some trolls can endure the light of the sun... and like you I like to think that these sun-resistant trolls are ONLY the Olog-hai.

So, I'm leaning into making Cave Trolls turn to stone in the sun.
Hill Trolls... well, maybe they are the Olog-hai. Sure they fought at Morannon, as it was pointed out
Mountain Trolls.. I don't want to think about them! Seriously, they are described as stupid, while Olog-hai apparently are pretty smart. So they can be of the traditional type.

[Otaku-sempai]

I think that Hill-trolls, Stone-trolls, Cave-trolls and Snow-trolls (and probably also the Mountain-trolls) can all be classed as Trolls of the Twilight and are all different from the Olog-hai. All except for the Olog-hai are relatively stupid and should be petrified by the light of the Sun according to Tolkien in the Appendices.

[Falenthal]

I think that Hill-trolls, Stone-trolls, Cave-trolls and Snow-trolls (and probably also the Mountain-trolls) can all be classed as Trolls of the Twilight and are all different from the Olog-hai. All except for the Olog-hai are relatively stupid and should be petrified by the light of the Sun according to Tolkien in the Appendices.

That's exactly the way I play them. I can't assure where the information can be found, but if Otaku says so, I believe him.