Apocopocolypse Now

Very easily farmed, albeit a bit time consuming. Available once you have researched [order-advancement=1932].

Equip an item with [spell=364480] if you have it. This can be found on the cloth shoulder pieces, leather shoulder pieces, mail head pieces, and plate chest pieces with the cypher equipment tag (such as [item=190992]).

When you encounter a coreless automa, tell Pocopoc to control it (Requires 1 energy to do, but does not actually consume the energy if you have the above ability), wait for the automa to actually start following you (important to avoid causing a bug preventing you from dismissing it), and then tell Pocopoc to leave. Proceed to the next coreless automa and repeat.

Waypoints of coreless automa:

/way #1970 33.2 56.2 Coreless Vombata
/way #1970 37.2 37.6 Coreless Vombata
/way #1970 37.8 47.2 Coreless Vombata
/way #1970 38.4 70.8 Coreless Vombata
/way #1970 45.4 75.8 Coreless Vombata
/way #1970 46.8 78.6 Coreless Vombata
/way #1970 56.0 66.6 Coreless Vombata
/way #1970 32.6 59.8 Coreless Helicid
/way #1970 37.2 70.8 Coreless Helicid
/way #1970 37.8 55.0 Coreless Helicid
/way #1970 42.4 88.2 Coreless Helicid
/way #1970 43.8 61.2 Coreless Helicid
/way #1970 44.4 56.4 Coreless Helicid
/way #1970 50.0 62.6 Coreless Helicid
/way #1970 52.6 75.0 Coreless Helicid
/way #1970 59.0 84.2 Coreless Helicid
/way #1970 63.2 70.4 Coreless Helicid
/way #1970 42.6 43.6 Coreless Scarabid
/way #1970 40.8 31.6 Coreless Scarabid
/way #1970 44.4 36.8 Coreless Scarabid
/way #1970 47.6 24.2 Coreless Scarabid
/way #1970 51.4 49.2 Coreless Scarabid
/way #1970 62.0 32.0 Coreless Scarabid
/way #1970 67.2 25.0 Coreless Scarabid
/way #1970 41.6 27.8 Coreless Tarachnid
/way #1970 44.2 24.6 Coreless Tarachnid
/way #1970 53.6 27.0 Coreless Tarachnid
/way #1970 57.0 25.4 Coreless Tarachnid
/way #1970 59.0 49.0 Coreless Tarachnid
/way #1970 59.4 54.8 Coreless Tarachnid
/way #1970 62.8 62.4 Coreless Tarachnid
/way #1970 64.0 43.8 Coreless Tarachnid
/way #1970 47.2 46.0 Coreless Geomental
/way #1970 50.0 41.6 Coreless Geomental
/way #1970 53.8 90.4 Coreless Geomental
/way #1970 55.0 60.4 Coreless Geomental
/way #1970 66.4 38.0 Coreless Geomental

Here's a macro that puts a skull on the nearest available Coreless mob (within range), sounds a raid warning (just to you) and whispers to you in chat that you've found one. Keybind it and just fly around spamming the key. Don't forget to change trojanhorse to your character name!

/tar Coreless Vombata
/tar Coreless Helicid
/tar Coreless Scarabid
/tar Coreless Tarachnid
/tar Coreless Geomental
/stopmacro [noexists]
/run SetRaidTarget("target", 8)
/w trojanhorse FOUND
/run PlaySound (8959, Dialog)
/stopmacro

Make sure youre not flying (Pocopoc on his flying disc too) when ordering him to take over the automa. He will not get inside of it and grant you progress for the achievement, you'll only spend his energy.
Being mounted while on ground works fine.