Mellyrn

Melrein was the Elves' original capital city destroyed by Jibril. By the time Riku visited it, Melrein contains collapsed structures woven of trees. Although the ugly burnt marks remained, the ruins were blanketed in brilliant flowering plants like a graceful garden. In the world of death where the sky was stained the color of blood and the earth was sullied by the poison of the black ash, it appeared that the fallen metropolis still enjoyed the protection of an Old Deus. More specifically the protection of Kainas, the God of Forest and the creator of Elves.

Elven Library
According to Fiel, the library was full of magical grimoires that were stolen by Jibril during her attack and raid on the Elves' ancient capital. It was relatively intact compared to other structures as the elves prioritized in protecting it during the attack.

The top floor and entrance is a "rooftop garden" with a "field" of flowering plants, while fungi clustered around pillars inscribed with elvish dotted around the garden. The Áka Si Anse test reactor was hidden beneath the library, disguised by multiple spells.

Áka Si Anse Test Reactor
The first prototype of Áka Si Anse was developed using the core of captured Insein Nebia and fielded under the city, in which Think Nirvalen intended to use it to blow up the center of the capital along with the invading dwarven fleet led by Lóni Drauvnil. However, it was never deployed as Jibril nuked the capital with her Heaven's Strike before that could happen. It was discovered by Riku and Schwi years later.