Cato Neimoidia
The Eastern Arch: 8 Holocrons
Holocron #7 Saber Crystal: You could easily miss this holocron as there is no reason to go to this landing platform. Make sure to head to the empty platform at the beginning of the level on the opposite side of where you start before you head into the elevator after defeating the enemies. It will be behind a stack of crates.
Holocron #8 Experience Point: When you come across the transport platform, you will need to turn around and move 3 elevators to climb to the upper area to progress through the level. Climb to the right side to reach the XP Holocron sitting in plain site near the edge. If you go to the left side, you can still get this XP Holocron by walking all the way around.
Holocron #9 Saber Crystal: You will come to a point where you need to Force Push a door to bust it open. It will immediately be to the left as you exit through that door you just forced open.
Holocron #10 Saber Crystal: This one will be shortly after Holocron #9 and the next time you enter another room with a globe in the center of the room. Move the glowing globe with the force and grab the Saber Crystal.
Holocron #11 Blue Bacta Tank: It is an unmissable holocron but you may miss it while you jump because of the angle you are at and if you jump to early or late. If you do not get it, die right away and you will restart right at this same spot. If you get it, but die, it will still be counted that you got it and you can proceed to the next holocron and/or continue to play. It will be near the middle of the walkway as the gunship is shooting at the bridge destroying it as you move along it.
Holocron #12 Green Bacta Tank: It is an unmissable holocron. Once you Force Push through the door you will see it above walkway ahead of you with stormtroopers on each side of it shooting at you from a distance. Jump onto the empty platform and perform a double jump and dash to reach the walkway and this upper area.
Holocron #13 Experience Point: It is an unmissable holocron. It will be right after you drop down another elevator shaft and on an upper platform in clear site at the center of it.
Holocron #14 Costume Holocron: This is an easily missable holocron. It will be shortly after you drop down the last elevator shaft and when you encounter the entire casino floor with smoke. You will battle a Carbonite War Droid along with some Sith Acolytes and stormtroopers. Once you force push through the carbonite door, head all the way down and you will see a Jaba the Hutt hologram, destroy the 3 casino machines here and the Costume Holocron will appear inside of the hologram.
The Western Arch: 4 Holocrons
Holocron #15 Experience Point Holocron: This is an easily missable holocron. It is located right where you start in this level which is just after the cutscene from when you were on the transport. It will be behind the docking clamps.
Holocron #16 Saber Crystal: This is an unmissable holocron. It will be on at the start of the 3rd walkway you come across as you move through the area just after collecting Holocron #15. You will need to use one of the nearby crates in order to jump and grab it, as I show you before and after in the video. Holocron #17 is coming up right after this upcoming fight after collecting this holocron too.
Holocron #17 Blue Bacta Tank: This is an unmissable holocron. It will be in the room to the left as you first enter with the globe in the center just after the battle you fought with a Carbonite War Droids and stormtroopers.
Holocron #18 Green Bacta Tank: This is an unmissable holocron. It will be in the center of the walkway when you get to the last barricade with the Carbonite War Droid and stormtroopers.
The Tarko-se Arena: 2 Holocrons
Holocron #19 Experience Point: This Experience Point Holocron will be on the 3rd level as you proceed up the elevator. You will need to double jump and then dash towards this area to grab the holocron. You can stay in this area and jump down below to a small platform to grab Holocron #20. Watch the next video on how to exactly grab Holocron #20. Make sure to not stay on the elevator too long, as it will then lead you to a cutscene and to the actual arena where you will fight a boss. You will not be able to go back unless you later reply it.
Holocron #20 Saber Crystal: This Saber Crystal Holocron will be on the 2nd level directly across from where you start. If you are still at the area where you just collected Holocron #19 then drop down below to a small. Then perform a double jump and dash towards the 2nd level where the Saber Crystal is at. If you fall just rinse and repeat by taking the elevator up to the 3rd level. Make sure to not stay on the elevator too long, as it will then lead you to a cutscene and to the actual arena where you will fight a boss. You will not be able to go back unless you later reply it.