The newest nation is Sumeru that got relased.

I think its pretty cool, im personally a desert fan because of tue informations about the twins.

Sumeru is one of the seven regions in Teyvat. It is the nation that worships Lesser Lord Kusanali, the Dendro Archon.

It is renowned as the center of learning and houses the Sumeru Akademiya.

Access to Sumeru is unlocked after completing the Archon Quest Prologue: Act I - The Outlander Who Caught the Wind.

Archon Quest Chapter III: Truth Amongst the Pages of Purana takes place in this region.

Sumeru's landscape features both deserts^[2] and forests.^[3][4] In the Teyvat Chapter Storyline Preview, Dainsleif likens it to a desert, and Liben mentions that "Sumeru is all rainforest and desert".

500 years ago, during the cataclysm, the previous Dendro Archon was slain^[5] and the current God of Wisdom took their place.^[6] Under the aegis of the God of Wisdom, the sages of Sumeru drive themselves into hysterics and abandon all that is worldly in their pursuit of esoteric wisdom.^[3]

Lisa went to study magic at the Sumeru Akademiya, where she was considered the best student they had seen in 200 years. Despite the prestige she enjoyed there, she ultimately returned to Mondstadt after growing disillusioned with the "raving-mad scholars" and the cost of "uninhibited erudition" she witnessed in Sumeru.

The Eremite are a faction of mercenaries from Sumeru who travel throughout Teyvat.^[7] They see themselves as people who are not "afraid of dying so that they might truly live."^[8] Nazafarin, a scholar from Sumeru, claims that some of its members wield "bizarre yet formidable powers," and finds the subject of the Eremite unpleasant enough to swiftly drop the subject after briefly explaining them to the Traveler.^[9]

Sumeru's Statue of the Seven depicts a female figure who appears to be a child.^[10] She is shown to be wearing a similar cloak and draping clothing similar to the other known Archon statues. Her small frame is also shown sitting on a huge leaf, an attribute owing to her mantle as the Dendro Archon.