When in Ihgaluk, Do as the Skumblade Do

Kroshik advances through four phases of life during a week's time. Each phase lasts 4 days. Yes, this means only one piece of the achievement will be up every few days. He goes through the cycle chronologically.

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• [npc=69907] (Egg) can be found as an egg. (Spawns at [51.3, 71] in the dragon skull which is also [npc=69997]'s spawn point.)
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• The baby [npc=69908] (Baby) will hatch from the egg and can be found running around Ihgaluk Crag. (I found him walking down the path from Progenitus. He doesn't seem to pat to far from there.)
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• [npc=69218] (Mature) matures to its adult form and will circle the filth pit/pool in the middle of Ihgaluk Crag.
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• [npc=70226] (Sacrificed) will be placed on the altar at the beach [55.0, 88.3] and sacrificed.
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On my server, Kroshik was in his mature adult phase on 5.2 launch so I do not currently have exact locations of the other phases. I will update with more information as I get it.

Updates: Day 2 of 5.2 and Kroshik is still in his mature adult stage. Day 3: Kroshik is still in his mature adult phase. Day 4: Kroshik is still in his mature adult phase. Day 5: I found Kroshik being sacrificed on the beach today (where the "Echo of Kros" boss can be summoned as noted by Paperdolls below.) I think it should be now safe to assume the "Mature" phase is 5 days. Day 6: This will be my last update for a few days. Kroshik was still in his sacrificial phase today. So I assume he will be this way for the next 2 days as well. If nothing changes, my next edit should be about the egg phase. :)

Edit: Added the egg's spawn point. (Thank you to Donlightbringer for the coords) Changed some original posts to reflect correct lengths of time and info. Added in the final phase info.

You can add all four versions to NPCScan to ease your life,

via ingame chat / macro:
/npcscan add 69907 Kroshik egg
/npcscan add 69908 Kroshik baby
/npcscan add 69218 Kroshik mature
/npcscan add 70226 Kroshik corpse or
by adding them to "_NPCScan.lua" file in /WTF/Account/ACCNAME/Realm/CHARNAME/SavedVariables/ directory:

[69907] = "Kroshik egg",
[69908] = "Kroshik baby",
[69218] = "Kroshik mature",
[70226] = "Kroshik corpse",

Ok here are the all 4 forms of Kroshik and where you can find it.

Kroshik Egg: It is hanging on the jaw of a dinasour skull where you kill the rare Progenitus...
Baby Kroshik: It roams around the area in Ihgaluk Crag where a subset of his route includes the ramp to Progenitus and the caves beneath Progenitus.
Adult Kroshik: It roams around the pool of Ihgaluk Crag, the hardest form of Kroshik to miss :)
Sacrificed Kroshik: It is deadly layed down on the altar near to the southern shore where you use your stones to spawn the boss.