The main lore change centered around an event called the Spellplague in 1385 DR. This cataclysm was unleashed when the goddess of magic Mystra was killed, transforming whole nations and altering creatures. In addition, parts of Toril have fused with its long-lost twin world Abeir, whisking away some countries and adding new ones. The Underdark is more open to the surface. Thay has become a nightmare land of death and the Elves, sensing the newfound connection to the Feywild, have returned to Faerûn in force. The event moved the fictional world's timeline 94 years into the future to 1479 DR. The Spellplague acted as a narrative justification for design changes.: