The Blackstone Spike was an incident that happened many years ago that ended up being one of the many contributing factors leading to war. Arguably, the blackstone spike was one of the biggest reasons war broke out.
This entire incident involves the precious gem indigenous to Avaris, the enigmatic Blackstone. Originally mined from the deposits found near Pereshka, Blackstone had a very unique appearance. However, the time when it was considered fashionable was long gone, and by and large the existence of this precious gem was forgotten.
In an expedition just outside Southwind, a group of inexperienced Magicians stumbled upon a very curious discovery. When fooling around with their new and exciting magical abilities, they stumbled upon the realization that Blackstone had the ability to dampen magical energies thrown at you. This was discovered quite by accident, as one of the magicians just happened to be wearing a ring made with Blackstone.
Unsure what to make of it, the group of magicians reported this news to the citadel situated in Southwind, which happened to house a few experienced Wizards. After a few quick tests it became clear that this curious gem actually possessed incredible power.
News of this spread like wildfire. While Blackstone was not a very expensive gem at the time, it was certainly not very common. Most of the Blackstone that existed in Avaris had been mined from Pereshka many years ago, and no other major deposits had ever been discovered.
Within days of this discovery, the value of Blackstone had risen by a staggering 10000%. A simple Blackstone ring that might have fetched a single gold coin now cost the entire fortune of a city's treasury.
Up until this point, magic was thought to be the only counter to magic. With Blackstone being another solution that was applicable in many more situations, many of the monarchs started looking all over to acquire Blackstone for their armies, afraid that other monarchs would have the upper hand. This specifically happened in both Felandur and Krakus, with both Mertheim and Athantor preparing their armies for an incursion into the territory of Pereshka. Pereshka had always been a neutral territory approximately halfway between the Elf and Dwarf capitals, but now with the possibility of being able to mine more Blackstone presenting itself, both armies prepared to occupy the ancient city.
Glinss, while being somewhat isolated from the rest of the continent, also was sent into turmoil. While Faerie society largely were happy with isolation, with the discovery of Blackstone's powers, there was a large growing desire to end the isolation and attempt to fortify themselves as well, due to the fear of being left behind. Pelinn, the faerie queen at the time, was the one largely responsible for this isolationism, but even she sent out parties to scout Pereshka and to attempt to locate other deposits of Blackstone. Pelinn also famously asked her subjects to turn over any and all Blackstone to the royal treasury to consolidate it all. Many refused, which caused turmoil and made Pelinn very unpopular. The chaotic situation at Glinss was probably what caused the Faerie armies to be completely unprepared for when the war came to an abrupt end.
Zyrustalo, the human monarch was caught completely unaware and had little to no Blackstone available to him. Afraid that this would lead to his downfall, he withdrew from the public eye and tried to come up with a solution quickly. Of course, his eventual plan was to convene with the Netherworld to bind the powers of the Djinn under him, which did allow him to ultimately bring the continent to their knees.
However, the biggest winner of the blackstone spike was Volvarto, the goblin monarch. A long time collector of precious gems, Volvarto found himself in the possession of countless pieces of Blackstone, making him the richest individual in all of Avaris. Not content sitting on his wealth, he hired the best armoursmiths in Dulkrag to craft a body armour made entirely out of Blackstone, reasoning that such a high concentration of the gem would result in very high magical dampening. He was right, of course. That body armour was the legendary Spellbreaker and it made him completely impervious to magic. For the first time, the goblins felt they had a very good chance to defeat both the Elven and Dwarf armies and entered into the conflict, aiming to capture Pereshka for their own.