You need to find 80 runes if you want to complete the Hidden Messages (10 runes), Footsteps of Idris (20 runes) and Vassa's Triumph (50 runes) challenges.
Below is a list of runes that can be collected during outdoor freeplay. So far I have found 72 places outdoors, where arcanist runes are located.
More runes can be found in dungeons / hidden places. Unfortunately, not all of the runes in the dungeons count towards the challenge. I am not sure whether it is a bug, random or intentional. "Bad" runes are a bit greener and have a slightly different shape.
I personally managed to find the following runes in dungeons (freeplay), but I'm not sure that every player will find the same type of runes.
- The Necropolis - 4 "good" runes
- The Foundry - 1 "good" rune, 3 "bad" runes
- The Hollow - 2 "good" runes
- The Shrine - 2 "good" runes
- The Bane Engine - 1 "good" rune, 2 "bad" runes
- The Core - 3 "bad" runes
- The Sovereign Mine - 1 "good" rune
- The Vault - 1 "good" rune
- The Dungeon - 3 "good" runes
- The Mandible - 1 "good" rune
- The Well - 1 "bad" rune
- The Haven - 1 "good" rune
