Raulothim was an emerald gem dragon and one of the most powerful mortal beings on Toril.
Raulothim was a solitary elder dragon who actively avoided contact with others. However, he was also highly curious, had a love of flying, and hated feeling left out. He enjoyed spying on people and important events from afar, never speaking to anyone and flying away if approached, thus earning the nickname "the Silent Shadow." Even if he never got close enough to understand the context of the things he saw, he was content merely bearing witness.
After encountering a spelljammer crew near his lair, Raulothim grew more introspective and fearful. He was deeply concerned at the implications of gate magic, wondering how many different worlds existed, and how many powerful spellcasters they contained. As his paranoia grew, Raulothim stopped ranging far afield of his lair, preferring instead to remain at home and lose himself in deep contemplation. He resolved to gather up as much magic as he could—even if he could not master it all, he felt safer keeping dangerous items and spells from potential enemies.
Raulothim was concerned that Faerûn might become embroiled in a war between factions of "creatures from elsewhere", or potentially invaded by interplanar forces. He urgently sought to establish of some sort of surveillance network to monitor gates and portals for potential threats to the world, and hoarded magic items that would help him survive a potential conflict.
For more lore see:
Wyrms of the North