Greyhawk campaign update

After running Robert J. Kuntz's "Dark Druids", module "I1 - Dwellers of the Forbidden City" and Carlos A. Lising's "A5 - Kill Marquessa!", the first two set in the Suss forest and the last one on the northern coast of the Pomarj, in which the party discovered clues, but not explored, of a lost Temple of the Eye, recovered the Urn, killed one of Markesa's clones and raided one of her strongholds (where they killed Sturm Bucholtz but Markesa managed to escape), they returned through Celene to their lands in Verbobonc. Oh, by the way, I made Markesa a drow, as if all her wickedness and evil were not enough. 

During their stay in Celene they became acquainted, through Countess Tillahi, whom they've rescued from the Temple of Elemental Evil in the past, with Melf Brightflame. They left with them the Urn and a map they've captured from Markesa's stronghold for further study. Not long before they received a letter to travel back to Celene. Melf had devised the possible location of two other Temples of the Eye, one in the Jotens Mts. near SW Sterich and the other in the Hellfurnaces Mts. to the SW of the Yeomanry. The party agreed to investigate them and they traveled to the neighborhood of the first site through a magical mirror at Countess Tillahi's estate.

The idea behind the different Temples of the Eye (under the Temple of Elemental Evil, in the caverns of the Dark Druids, in the dungeons of the Steading of the Hill Giant Chief and bellow the Halls of the Fire Giant King) come, except the one in Dark Druids, from Greyhawk Grognard's series of posts about the Elder Elemental God.

Now I'm running a kind of "Return to..." of module "G1 - Steading of the Hill Giant Chief", in which the place above has been raided by a previous party and killed most of the giants (some escaped), and below the ogres and orcs revolted against the remaining giants and bugbears. The orcs chopped the heads of the hill giants and put them on pikes around the steading. This has been loosely inspired by a short fiction story called "Return to the Steading" by Bart Carroll that appeared on Dragon+ issue 11. 

So far the party has killed the ogres, charmed one of the three orc leaders and bribed the other two with part of the ogre's treasure (mostly copper coins, copper ingots, cheap jewelry and false gems). That way the orcs, that are able miners, agreed to clear the path to the sealed temple. Meanwhile a frost giant envoy mounted on a mammoth and escorted with two winter wolves showed up with a message to Chief Nosra. 

An epic battle ensued with the party victorious, although some gravely wounded, with one of the cavalier' retainer unconscious and his warhorse dead. The thief managed to decipher the message: a conclave of giant chieftains will take place next full moon in the Halls of King Snurre, and Chief Nosra should attend "using the gift and following the instructions". The party will now have to find out what that gift is and how to use it.