All of Omega will need to be unlocked because each of the three theirs drop a mount. The unlock for Omega starts with The Hunt for Omega in Rhalgr's Reach from Wedge (12.6,12.4) it is long like Alexander having to do all 12 raids in order for them to be unlocked along the way there will be a quest at the end of each their for the savage version.
Deltascape V4.0 - Alte Roite
https://www.youtube.com/watch?v=oEPGZvEJG1E

Sigmascape V4.0 - Air Force
https://www.youtube.com/watch?v=LnQZRLK0lIE

Alphascape V4.0- Model O
https://www.youtube.com/watch?v=Ec0rXCDZ-Mw
Deltascape V4.0 - Alte Roite
https://www.youtube.com/watch?v=oEPGZvEJG1E
Sigmascape V4.0 - Air Force
https://www.youtube.com/watch?v=LnQZRLK0lIE
Alphascape V4.0- Model O
https://www.youtube.com/watch?v=Ec0rXCDZ-Mw