Influx can give you a dex advantage, but it won't allow you to shoot first.   The clone always shoots first, and influx has nothing to do with his accuracy, only yours.  In my experience he will hit you at least 80% of the time.  It probably depends on your accuracy but I'm not certain about that.  Do you have a particularly impressive accuracy percentage (>90%)?  

There is no way to kill him reliably without a trignet.  A hit will keep him from attacking the first h2h round and give you a strong hp advantage.

Action combat is really the only way to do it, because you have to hit him every round.  One miss willl wipe out your advantage, because he almost certainly will hit you.  The last thing you want is to die at that level.

I believe the guard's bravery is your bravery.  If you have a particularly low bravery percentage you might find it impossible to kill him.  

Attempting to fight without armor will deplete your medkits much faster, because when the guard hits you with his trignet (most of the time) you'll have to run away and heal up that much more.  Armor isn't really worth cloning.  

The best item to clone is the alien device.  It sells for 95k.  A player spending lots of time in the afb shouldn't have a problem getting one.  I would not recommend cloning things like eggs, keys, and medkits.  It is a huge expense to pull off cloning, not to mention a huge risk, and when it works you want to pull in the most possible cash.  Selling a trignet and 6 alien devices at the afb nets you ~650k.  I know of no other way to make that kind of cash in a single turn.

The "best" is combo the Xendrix/Herculean.  Now best is since quotes because that isn't entirely true, but since I have access to the source code I've been sworn to a bit of secrecy.

Hopefully someone else will jump in and add the additional info.

The most damaging hand-to-hand weapon is indeed the Xendrix, although I'd argue the best is the Hydra-Jack because it doesn't need ammo.

The best long range weapon is the Trignet.  Herculean is second best.  Not only does the Trignet do the most damage, but if the shot is on target it disables the enemy for one attack, whether long range or hand-to-hand.  This is pretty much the only way to fight guard clones and win.  But that's another story...

The problem with the trignet is that only one monster carries it (Diabla, level 4) and only with one shot, so if she drops it you get a trignet with no ammo.  The only way to use a trignet is to buy ammo for it in the afb research room at incredible cost: 95000 for 50 rounds.  The trignet without ammo costs you 130000.  I believe ammo and weapon prices in the research room are in the faq (which is in need of serious formatting help, btw).

Just to round out the combo, the best armor is Polycarbon.  A few monsters have it, eg Orkaner in the AFB, or it can be bought in the same place as Trignet ammo.

If the Herculean really is the best long range weapon, wouldn't Overkill use it?

No problem.  I can't say how long the link will be valid though - probably about a year.

The Players Guide posted in the downloads area is an outdated version.  Until it's posted on the site, the newest version can be downloaded here: http://www.utdallas.edu/~grantr/files/oofaq.zip.  It's still fairly old (been a year and a half since .16, the most recent) but the one on this site is positively ancient.

There's lots of new stuff in the new one, so check it out.  My favorite addition is probably the stuff about item cloning.. very dangerous, but by far the quickest way for high-level players to earn crystals.

Just like the download description says, this document lays bare pretty much every secret in the game.  If you want the satisfaction of finding all this out yourself, don't look (but be prepared to get pounded by everyone else).

Tarix, if you could post this new one on the website, that would be great.