Bounty Hunter 18 (Source)
Arakyds = your interplanetary search. This is the first step in your search for your mark, because it tells you which planet he is on. Interplanetary searches don't come into play until Investigation-2. Seekers = your search after you're on the right planet.
When you first start out at Novice BH, your SpyNet operative gives you a waypoint to your mark. At Investigations 1, you start using Seeker Probe Droids. The mark will still be on your planet of origin, but you won't get a waypoint to him. Instead, the SpyNet operative gives you a "biosignature" sample from the mark, supposedly culled when he uses a public shuttleport or starport terminal. Once you do that, you can then use a Seeker droid (the black spheres used by Darth Maul to locate Queen Amidala in Episode 1, and you can buy Bounty Hunter droids from a droid-engineer vendor) to locate your quarry. At that point, you'll activate a waypoint.
At Investigation-1, your mark doesn't move around, so tracking him down is still relatively straightforward.
Things get much more interesting at Investigations 2, because two things are now changed: Your marks can now show up on any planet; and they move! Unfortunately, you don't unlock Droid Tracking until Investigation 3.
So, the drill for Investigation-2 missions is as follows:
1. Get your mission from a mission terminal 2. Consult with an intermediate-level SpyNet operative (the level-2 guys) and obtain a biosignature 3. Travel outside the city limits, then call down an Arakyd Probe Droid from an orbiting starship. These are the bulbous-headed droids that crash-landed on Hoth in search of the rebel base at the beginning of The Empire Strikes Back. 4. When it crash-lands near you, move to it, pull up it's radial menu, and select the "Transfer Biological Signature" command. It acknowledges your input with a message that it's commencing an interplanetary search and zooms into space. 5. After about a minute, you will receive a message, either some sort of malfunction like "Your droid has been destroyed by a comet" or "Your droid has exploded in space," or that it has located your mark on such-and-such planet. You then travel to that planet. 6. When you've landed on the correct planet, you will notice that you now have a waypoint. It is now your unhappy task to travel to that waypoint in the hope that your mark will be there. Chances are he won't be, because as I said earlier, they now move. 7. When you reach your abandoned waypoint, send up a Seeker Probe Droid. After a moment, it will activate a new waypoint. Go there, and see if he's still there. He probably won't be, so repeat this step as often as needed until you catch up to him. 8. Eliminate your mark, and collect your reward and PHAT xp bonus! (phat, it is not!)
Now, let me translate those Droid Efficiency and Droid Speed numbers for you.
The higher your Droid Precision, the less likely your droids will malfunction. This means a lower chance that your Arakyd will blow up in space, be eaten by space slugs, be struck by a passing comet, or whatever. Basically, it reduces your aggravation level. Droid Speed improvements will reduce the time you spend waiting for your information from both Arakyds and Seekers. The "tracking" commands and bonuses come into play at Investigation-3.
Investigation-2 is the most tedious of the BH grind levels, because you need to run a lot of missions, and your target is on the move and your droids don't track their movements.
Once you get to Investigation-3, you'll feel like a huge load of weights have been taken off your shoulders! Now your Seekers will begin to automatically update your on-the-move target's location! Huzzah!
At this level, the tracking modifiers come into play:
- The higher your Droid Tracking Speed modifier goes, the faster you receive updates on your target's position. (By the way, Arakyds do not track your targets. Only Seekers do.)
- The higher your Droid Tracking Effectiveness, the more reliably they work
- The "Tracking Droids +n " modifier does not give you more tracking droids. Rather, it increases the number of updates each Seeker Droid gives you before it loses track of your mark. For example, it's +4 per level at Investigation-3, -4, and Master Bounty Hunter, meaning that a Master Bounty Hunter will top out with 12 updates for each Seeker he sends up.
I haven't seen a skill tape for these skills, but that doesn't mean they're not out there. You can also buy bioengineered clothing that will give bonuses to droid use.
Happy hunting!