Seven rift battles, each on a different element - Ice and Light have none. You start them from the “Strange Rifts in Idyll” activity, 1-4 players, everyone pinned to Lv 30, five rewarded runs before it refreshes. Each one belongs to an Alpha and drops that Alpha’s element stone; the rest of the pool is the same everywhere, and the first clear pays more than every run after it.
The seven territories
Stellarys TerritoryAlpha Stellarys · Night Stone
Scorchhowl TerritoryAlpha Scorchhowl · Blaze Stone
Panpanta TerritoryAlpha Panpanta · Wave Stone
Blazen TerritoryAlpha Blazen · Roar Stone
Irisal TerritoryAlpha Irisal · Sprout Stone
Turbo TerritoryAlpha Turbo · Gust Stone
Minespine TerritoryAlpha Minespine · Loam Stone
Stellarys TerritoryAlpha Stellarys · Night Stone
Scorchhowl TerritoryAlpha Scorchhowl · Blaze Stone
Panpanta TerritoryAlpha Panpanta · Wave Stone
Blazen TerritoryAlpha Blazen · Roar Stone
Irisal TerritoryAlpha Irisal · Sprout Stone
Turbo TerritoryAlpha Turbo · Gust Stone
Minespine TerritoryAlpha Minespine · Loam Stone