If i finish embattled retreat (mylarai chain) will the Octafari leviathon never show up?

I am half way through and havent had a single Leviathan but want to get my 4 rift emitters. I want to finish the chain asap though so i can be mylarai.

when the mission ends, the leviathans dont spawn anymore. make absolutely sure you get all 4 before you finish the mission. otherwise you miss out.

sigh, if i could send them to ya'll i would. was too lazy to finish the mission and ive had literally hundreds since :/

Ok i have now nearly finished the mission just got the last completion to do and have only foiund 1 leviathan. My scan is at 1100 do i need more scan to see them i think i have fought over 500 npc trying to get them to spawn!

nope, it's just a very uncommon "uncommon" spawn...

do you have any other missions that require hunting for uncommon spawns (like the dark iso-runners from Potent Residuum) ?? cuz those cut into the chance of your leviathans appearing

Yeah i have the dark iso runner turning up aswell. Its a real pain Thanks for the tips