1

 Whole Truth: The Duladarin star elves, then the Al Nasar gold dwarves, then the Yugtug greenskins, and the Raceon humans used to dominate the Luna Valley before the Ice Tongue Glacier formed. Each civilization was wiped out by the same mysterious disease.

2

Partial Truth: The Duladarin star elves, then the Al Nasar gold dwarves, then the Yugtug greenskins, and the Raceon humans used to dominate the Luna Valley before the Ice Tongue Glacier formed. Not sure why each one left the valley.

3

Truth and Lie Mixed: The Duladarin star elves, the Al Nasar gold dwarves, the Yugtug greenskins, and Raceon humans used to live together in the Luna Valley before the
Ice Tongue Glacier formed and crushed them all to death.

4

Lie: The Duladarin star elves, the Al Nasar gold dwarves, the Yugtug greenskins, and Raceon humans used to live on another plane. They angered the gods in some unknown way and the gods wrapped them in ice and sent them hurtling through the multiverse. That ball of ice was the Ice Tongue Glacier which landed in the Luna Valley. That’s why so many ruins were frozen under the ice.