The Three were the first three known arcanists who had found the secrets to achieving lichdom. These first three liches sought to enslave the entire continent to their dark, twisted, undead whim, and raised a large force of undead. They struck in the north, first, catching the Arborlonian elves completely by surprise. Many elven towns were wholly razed and destroyed. Arborlon itself was only saved when the Elven Enchanter Neravenwyn Silleastril sealed the entire city in a protective cocoon of magic, thwarting the Three, but preventing the elves from being a force in the region for ever more. The seal would not be broken for 100 years.
The Dyninn was not the only region ravaged by the three. In the south, the liches seiged Paragon, the seat of the King, for fifty years. The city held off, but was cut off from the rest of the world; only the work of the wizards and clerics in the city kept the city from perishing. The Bloodcoast was mostly spared, but only because of the deals the Marquis of Arroch made with the three.
Astalon was nearly sacked. The southern breadbasket was almost entirely wiped out. Famine and disease ran rampant. The population of the continent was reduced to almost a third. The advancements of the previous ages were almost all nearly lost.
The three spread terror and death for nearly fifty years. Their sacrifices of creatures to their war machine was feeding an elaborate spell, designed to give them godly powers. On the eve of the completion of the spell, an alliance of wizards, numbering in the thousands, faced off against the three. Only 1 in 100 survived, but the three were destroyed, wholly and utterly. From then on, the wizards of the realm formed the Guildtowers, and pledged to protect the continent of Muriah from further magical threats.