I have covered this datacron extensively in a different guide outside of the main datacrons guides, so please check it out!
Ossus Green Endurance Datacron Guide
The Ossus Green Endurance Datacron is located in the Jedi Temple Ruins map on Ossus grants Endurance +2.
The Ossus Green datacron is in the hidden area of the jedi temple, accessed by an extremely hard jumping puzzle and is available to both Imperial and Republic players. Finding this datacron will give you a permanent stat boost of Endurance +2 to all your characters on your server, and will unlock the Ood Bnar codex.
Ossus Endurance +2 Datacron (Both Factions)
Quicktravel: 
Jedi Temple Ruins / 
Jedi Temple Ruins
Taxi: Jedi Library / Jedi Library
Location: Jedi Temple Ruins - hidden area of the jedi temple, accessed by an extremely hard jumping puzzle
Difficulty: Very Very Hard - difficult jumping puzzle in the dark
Codex: Ood Bnar
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