Search for Spectres

So, 2 days ago I found in Necropolis Map some cool Undying Incinerators (level 75), that carried me for all the next maps with ease. Now the problem is, I can't find them anymore.. I ran Necropolis 2 times, also Crematorium and Cells where I saw them in the past.. NOTHING

I think High Level incinerators are by far the spectres with the highest DPS that is also very easy to boost and support, but they are so hard to find. I don't get why people can't keep their Spectres after logging out, it's not like it takes any skill to go and get them or to leave the PC On, which I did for a long time after I found them.

Isn't the Chance of losing them by battle already annoying enough?

Now how am i supposed to find these? they don't spawn all the time. I'm forced to use Sentinels now but their DPS is like 1/4 if not less...

Help :s?

I have had no summoner experience whatsoever so forgive me if this is wrong, but can't you use Desecrate to get the corpses if you're in a Crematorium map?

(Also, apparently GGG do want to make spectres persist through logout in the future, but it is a nightmare to implement. Edit: source.)

Desecrate gives you the corpses of the mobs that you can find in that area. sometimes they aren't there at all so desecrate wouldn't spawn them

that may also happen in eternal laboratory where you get the sentinels: sometimes (rarely enough) i have to create a new instance because sentinels just wouldn't appear

the reason is: there is a limited number of monster variety in any map.. and i think some mobs are rarer than others

oh thatnk for that info.. but i don't see that happening soon..