Shelly

To get [item=189378] you need to find [item=189446] in Zereth Mortis and bring it to the Synthesis Forge*, then collect reagents for the craft

How to get Schematic:

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2. How to get [item=189378] video: https://youtu.be/UVeWQFQGb5c
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4. Location map: https://i.gyazo.com/f9270cff397b2e065d271395a87ff86d.jpg
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6. What to look for Img: https://i.gyazo.com/62e4d694bd6e7ebcc301daf4a1fb900b.jpg
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8. Inside the [object=375270] in Gravid Repose inside the Lexical Grotto 59.01 81.82 cave
   Enter the groto and move to the left book shelf (2-nd from entrance)
   It is behind the book shelf, and to get it you will have to use Door of Shadows or similar.
   /way 59.01 81.82 Lexical Grotto Entrance
   /way 57.92 78.01 Shelly (On the shelf)
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Resources required to craft (all of them are zone related):
400x[item=188957] - drops all over the Zereth Mortis
[item=189168] - need to find from open world objects with the same name
/way 50.0 11.0
/way 46.9 11.2
/way 64.7 63.4
/way 51.2 28.3
/way 43.0 35.5
/way 64.5 39.1
/way 34.4 71.3
[item=189145] - Can buy on AH or farm from specific mobs (check dropped by section)

* Synthesis Forge Prerequisites to be able to see a schematic & to turn it in & craft the Pet:
Complete 3 parts of the main campaign in the Secrets of the First Ones Forming an Understanding
Complete [npc=181397] upgrade [order-advancement=1904] => [order-advancement=1932] (to craft pets) & [order-advancement=1931] (to craft mounts)
Complete Protoform Synthesis quest to craft pets / Finding Tahli questchain & After daily reset The Lost Component & A New Architect to craft mounts
More detailed info can be found here: Synthe-supersized!
/way 70.18 28.60 Servitor Interface (Mounts Forge Location)
/way 61.97 58.93 Protoform Synthesis Forge (Pets Forge Location)
Right now you will need to complete the prerequisites to interact with the forge and turn in the schematic quests