I know there's a few threads already, but the info is spread out so sporadically, I just wanted to say that it's May 2017, and I just got the Sith Master achv, using cheats.
On Xbox One.
I did 2 legit playthroughs already, so don't bother whining to me.
* Start a new game on Sith Master.
* Play and BEAT the first level (as Darth Vader).
* Start playing the first real level as Starkiller.
In the hallways with the droids, before facing any enemies, enter your cheat codes:
These are the cheats I used:
KATARN All Force Powers Unlocked and Maxed
ADEGAN All saber throw ranks unlocked
JOCASTA All Talents Unlocked
LIGHTSABER Amplified Damage
RAGNOS Combo Unlock
MOLDYCROW Unlocks All Force Combos
(DO NOT USE: EXARKUN Maximum Force Push. Note: disables saves and may block some unlockables)
* Now you need to get to a checkpoint, so I played until I got RIGHT PAST the first room with the hanging Tie Fighters on the ceiling and you have to use force power to open the door (2 locks). Then the game saves.
* Go a little further and let yourself die (in the "communications" looking room with red omnicron in the center).
* When you respawn, manually SAVE the game.
* Exit to XB1 dash, force quit the game. (I've also read you can just go to main menu, but THIS is what I did and it worked).
* Start the game, DON'T click "CONTINUE GAME" - instead click "LOAD GAME" - and manually load your Sith Master game.
You will now have all the cheats still enabled, and you can still get achvs.
I ran through the entire game, speedrun style, on Sith Master, in 1 sitting. It took over an hour (maybe less than 2), because even fully leveled up, bosses just have so much health on Sith difficulty, it's time consuming killing them.(I read that the LIGHTSABER cheat does not save if you exit the game and come back - but I did in 1 sitting so I cannot confirm)
But MOST of the game, you can just RUN RIGHT PAST. You do not
need to kill 95% of all enemies! Every so often I would use FORCE REPULSE to kill large groups to refill my health, that's it. I really only killed bosses.6/21 EDIT: ANOTHER NOTE: Even after you beat the game, if you want to mop up other achvs, you can level hop and the cheats remain active.