How does Echo Raids work?

Question

I know that Echo Raids spawn immediately after server save in different subareas and that they also have a chance to spawn whenever a creature is killed.

So far, I have found 27 Echo Raids in 27 different subareas, plus 3 additional Echo Raids that appeared after killing creatures.

However, during the Test Server, it was reported that automatically generated Echo Raids could respawn approximately 20 to 30 minutes after the previous one was activated. Was this information ever officially confirmed, and is it still accurate?

Can Echo Raids spawn in every subarea in the game, or are there certain areas where they cannot appear?

For example, I searched the entire Isle of Evil and did not find a single Echo Raid there. I do not know whether raids are unable to spawn in that subarea, but it contains Common and Uncommon creatures, so in theory it should be eligible.

Could the raids perhaps be spawning in inaccessible locations?

I know that Echo Wardens and activated Echo Raids disappear after 10 minutes. However, what happens to the Echo Raids that spawn automatically after server save but are never activated? Do they remain there until someone finds them, or do they also disappear after a certain amount of time?

Answer 1

I can confirm echo raids respawns on the same hunt areas in around 20-40mins for example. Wyrms in Liberty bay depot is always there on the ground level, never spawned once in the stairs. I've spawned both Wyrms and Elder wyrms on both sides and wyrms only in the main cave.

Also I can confirm echo raids can spawn in inaccessible location, today I have found one echo inside Palomino corral Horses in Thais and for your last question I've been camping that echo for severals hours and seems it doesn't dissapear until is steped that means a new echo raid will never spawn again in Thais east surface SS.

It makes sense since I've noticed that most of the echo raids spawns after SS and early morning, but the closest we are of the SS echoes are harder to find(unless you spawn it by killing monster) meaning that in some point of the day most of the echo raids are spawned in a unaccesible zone.

Also I would add that echoes spawn are assigned to certain zones, for example back to Wyrms in LB Depot, that cave have 1 echo, but also 1 can be found in the whole bonelord cave in Liberty bay, can be found in any of the 3 levels but only 1. One more echo in Calassa for the whole area, 1 more echo for Greenshore and all north of thais(both shares the same echo) meanwhile another echo can be found in east of Thais, both north and east are part of Thais sorrounding sub area but have 2 echoes, in conclusion echoes have an specific zone to spawn and is not designed by the Map sub area

Answer 2

Echo raids seems to follow the same mechanism than fiendish in terms of what can or what cannot become an echo, if some fiendish is unreachable it can certainly become an echo raid.

yes, only 1 spontaneously generated echo can exist per subarea until it's triggered.

I doubt there's any special rule about which subarea can or can't spawn a echo other than the general rule of it being a common/uncommon creature, i will need confirmation tho, what i can tell you with certainty is that there are several subareas that share space with several other parts of content that you regularly will miss, a quick example that i noticed today is that haunted nexus is considered a whole subarea instead of haunted cellar tomb and temple, so only 1 echo appear between all 3, so sometimes we overlook that info.