since I FINALLY finished a proper ref of Thunderclouds, I thought it would be time to properly introduce him, so, here's this guy's lore:
Distant Thunderclouds is the fourth oldest member of the Eternal Glaciers Local Group (or, the second oldest if we only count the inner group), as he was built not long after Fading Echo was finished. The whole group was built on a tundra, but Thunderclouds specifically was built on the flatter areas as his can was built next to a large void fluid processing facility. He was created to oversee the operations at this facility as well as in his city.
For this reason, his creator, an ancient by the name of Twisted Spine, All Promises Kept (a total douchebag), wanted to make him as efficient as possible. But after the authority in charge of the creation of iterators refused to let Spine alter Thunderclouds's systems officially, Spine became frustrated that his project wasn't going according to his plan. So, instead of going through official channels to modify Thunderclouds's systems to become more efficient (efficiency basically meant a lack of empathy and free will, and the inability to commit any sins to Spine, because he was still a pretty firm believer in the old ancient philosophies and religion), he decided to do the modifications himself in secret. This, however, messed up Thunderclouds's systems pretty bad, as he had already developed the sentience that his creator didn't want him to have, and even attempting to modify it caused Thunderclouds a large amount of pain. After a while, Spine grew more frustrated about the whole situation and started taking his anger out on Thunderclouds, who, at this time, still saw Spine as a father figure, but was slowly starting to dislike not only Spine, but ancients as a whole.
Thunderclouds was also really reserved, and only spoke to most of his local group out of necessity. The only exception to this was Solemn Contemplation, the outer group's senior, who became kind of a mentor/almost a mother figure to Thunderclouds. He eventually managed to find a friend outside of his local group as well, an iterator by the name of Marble Blood, who aided him in finding ways to bypass his city's security protocols, which he would later use.
Still, his relationship with his creator only worsened, to the point where he'd be punished for simply talking to other iterators, as Spine still only cared about him as a tool, and slowly, Thunderclouds became frustrated by his situation, and grew hateful of the ancients inhabiting his city. And when a huge snowstorm disabled his communications for dozens of cycles, and he was blamed for being unable to call for assistance, he decided he had enough. He turned his city's security systems against its inhabitants, which resulted in the death of most of his can's population, including Spine. After the storm cleared, and the ancients of the other iterators' cities realized what happened, Thunderclouds was declared a hazard to the ancients, and his systems were disabled (he basically got his power shut off, causing him to go into a kind of coma).
A long time after all of this, and after the ancients all ascended, was when he finally got reactivated using a neuron that Ten Open Passages created, that he sent using a genetically modified slugcat (the icebound).
(And that's basically all his backstory, cause I don't have anything written down after that, so, that's it for now)