Posion, plague? Are you in Taris? Here's a walkthrough for all of Taris. Just scroll down until you look at the part you want. The total faq is
http://www.gamefaqs.com/console/xbox/file/556553/27168 so use a gamefaqs if you need any future help.
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4-B. Taris
NOTE: This section was done entirely from memory and as such may be missing a
few details. I apologize for any inconvenience this causes and will fix
any errors as soon as I play through the game again.
Primary Quests
The Search for Bastila
- At the lower city entrance ask about going down until the guard mentions
needing paperwork or being a guard.
- Go to the apartments and rescue the person being attacked by Sith guards.
Take the uniform from the Sith.
- Wear the uniform to get into the Lower City.
- Go to the Cantina and watch the scene with Mission and Zaalbar, then talk
to them so they leave for the Bek base.
- Go to the Hidden Bek base and talk to Gadon until you wind up going after
the prototype accelerator.
- Trade the Sith Uniform for the Undercity Papers when you ask about how to
get into the Vulkar base.
- Go down to Undercity.
- At the Undercity gate, offer to help save the person to get outside.
- Head to the sewers to find Mission. Agree to help her find Zaalbar.
- Down in the sewers, find and rescue Zaalbar.
- Go back to the force field generator and Mission will open it.
- Follow the upper level through to the rancor.
- Pick up the stuff on the skeletal arm.
- Go to the pile of bones and switch to give item. Put a frag grenade in it
and then one of the rancor prey odor sticks.
- Go through to the base.
- Disarm the elevator security system and go down the elevator.
- Get the garage head key from the office and go to the engine lab.
Light Side Dark Side
- Kill the Vulkar's in there and - Agree to kill Gadon for them.
take the Prototype Accelerator - Go back to the Bek base and through
back to the Hidden Beks. to the elevator. Go down and Gadon
- Agree to race the bike. will be there.
- Kill Gadon and the other Beks around
the base.
- Go back to the Vulkar Base and agree
to race the bike.
- When you're swoop racing, make sure you hit the acceleration pads and try
not to hit too many obstacles and you'll be fine.
- After the race you'll fight Brejik with Bastila's help. She joins after
you win.
Escape Taris
- When you're in control again, go to the Upper City Cantina and talk to
Canderous. Agree to his plan.
- Get T3-M4 from the droid shop. You can either:
- Pay the full 2000 credits for it.
- Use the first persuade option (offer 1000) to haggle her down to 1500.
- Use the other persuade option to threaten her and get it for free. You
will get Dark Side points if you use this option.
- Bring T3-M4 with you to the military base and have it open it for you.
- Access a security panel and view the elevator security camer. Spike the
door open. You can also disable the droid's shields if you want (it will
help a lot). Or go to the barracks on the east side and get the Sith
Passcard from the footlocker to unlock it.
- Make your way down to the lower level and fight the dark Jedi (well, almost
a dark Jedi, that has to count for something).
- Get the Codes and go to the Lower City Cantina. Talk to Canderous and tell
him you're ready if you are. Otherwise, finish up everything (you won't
ever be coming back after this point in the game) and come back later.
- Once in Davik's estate, go to the torture chamber and rescue the pilot for
the codes.
- Go to the Ebon Hawk. Don't worry about the fight, it will end on it's own
after a little while.
- Board the Ebon Hawk (don't forget to get the stuff from Davik's corpse) and
you'll be off the planet.
- Use the guns to shoot down the fighters coming at you and you're clear.