This is the only Dark vs Light Datacron that’s only available to a specific faction – Imperial players will not be able to get into the Shadow Town area to find this one.
Quick Travel / Taxi
The Republic [HEROIC 2+] Breaking Down Shadow Town is very close to the datacron, so instead of quick travel or taxi, picks up the Heroic and it will save you a long run.
Travel Deep into Shadow Town
Find the Crates
There is a large pile of crates hidden inside a caged area in the south west section of Shadow Town.
Jump up the crates until you get to a large caged walkway.
Follow the walkway until you see a bridge and cross it.
Across the bridge, you will actually see a blue datacron that is slightly different than the normal datacrons. This is called a “light vs dark datacron” and was part of a now-retired event.
If you keep following the pipes past this datacron you will be on the path of the jumping puzzle for the Red Nar Shaddaa Datacron.