Is there an easy way to kill this damn thing. It adds a level of difficulty, but good god it can take a beating. Any tips?

Use the gauss cannon or the vulcan, since they are hitscan weapons and it can not evade them. Try to herd the little f***er in a corner or a dead end tunnel and pummel it as much as you can before it escapes. Also, there is not much use chasing after it, find a good spot instead, somewhere that the bot can sneak behind you but will need a lot of time to clear away from your view after it attacks, and wait for it to come to you (which it definitely will).

That stupid bot is such an artificial difficulty device.
I can't travel the levels as fast as Descent 1 because of that bastard, sometimes it seems like a stop n' go thing; stop check if he is nearby,go,repeat. I agree, use your vulcan, homing missiles won't work because he moves too fast.

Save often, I end up saving my game more than in Descent 1 even when there is no enemies just in case the thief bot is nearby.

I don't know if there is one in every level.

I'm on level 22 and so far I've only encountered 1 maybe two levels where I don't remember seeing that son of a bitch. If I know that he is behind me somewhere I find a place where I can set smart mines, usually a one way tunnel, that might "discourage" him for wee bit.

So far I've only destroyed him about 4 times.

This and Mercury Missiles too.

Yeah, I hate this annoying robot so much. The Theft is a such tramp. Hehe!

LOL i know what you mean haha XD at least it has this buzzing sound to show that it is nearby. I hated that little bugger so much but it adds a bit of fun to the levels.

Nothing like fighting your way through a cave then all of a sudden your afterburners are gone, or your missiles, or guns.and then screaming "WHAT THE F***!!!!!!" lol XD

What I usually do is sit and wait for it, let it come to me instead, and unload on it with the Vulcan Cannon or better yet the Gauss cannon. It can outmaneuver most missiles, even homing, so save on that but mercury missiles do well. stunning it with flash missiles mmight work. Sometimes there is a lucky break where the thiefbot will go into a room with just one exit so you can trap it by being at the door and just shoot up the thiefbot whenever it comes near you =D

Just finished D3 and I have to say at least that damned thief bot is easier to kill. I still find myself trashing talking my monitor when I blow its little green ass up. So exilarating.

Thief Bot adds another five minutes to any level.
Once you know he's there, and he is after you, you go back to the start of the level, and herd him into that area. He can't get out usually. Flash Missiles and Vulcan early on. Helix cannon is pretty good too if absolutely necessary. :3

The Thief Bot does not appear on boss levels (every 4th level) so no need to worry about him then you have enough on your plate with the bosses as it is.

He can be ignored depending on what he takes from you. Sometimes he will steal your guided missiles (hard to use for the average player) and that can oddly enough be a welcome gift from this otherwise sadistic robot.

LOL My favourite to trap Thief Bot. What I do is upto 3 drop bomb close by the door and wait behind, ThiefBot will come to open the door and hit the bomb and shock spinning by bomb blast and shoot vauss oh him...ThiefBot is very wound lololol

I find booby trapping doorways with proximity bombs or smart mines works quite well for the thief bot. It will blithely barge through the door and cop your booby trap. This works on the DOS version - no idea whether it works on D2X-XL or any of the other ports.

If he stole something precious from you, or if you have a bunch of time to kill, go find an alcove, or preferably, a small room with only one door. Go hide in the room and stare at the door, but let go of the controls. If you idle long enough, he'll start taking risks, and come loiter near the room, and eventually he'll come in and try to steal somethin'. Shoot the hell out of him while he's trying to open the door to run, then just wait and set him up again. Works wonders.

I've gone through pretty much the entire game using the gauss cannon. There's just about enough ammo to use it through it too as long as you have half decent aim.
It's also the weapon you will devastate the thief bot with, in larger areas homing missiles do work well too. Mercury missiles in tight spaces.

Killed him on almost every level because I see it kind of like my primary goal to get rid of that annoying bastard as soon as I see him.

I've had him run up and steal stuff within 3 seconds of spawning into a new level too, then giving chase through large portions of uncleared station...chaos ensues lol

I agree it's a pain, but hitscan weapons do work wonders.

Homing missles are useless. Flash missles work well if you can smack them into a wall next to the critter. Take advantage of the stun to pummel it and nail it with another flash if you can.

Have killed it with lasers, plasma, and phoenix too ... just harder to hit.

If you can herd it into an area with doors it cannot open, the thing is toast.