The Robotics is, probably, the easiest class to play in Global Agenda if you know what you're doing. Unfortunately, it's also the hardest class to play well. There are nearly as many bad Robos in GA as there are bad Recons (more on that when I get around to writing my Recon guide). And it's for a simple reason: there's much more flexibility in the Robo class than there is in any other class. For Assaults and Medics and Recons, most of the choices of skills and equipment are obviously sub-optimal and won't be chosen. Not so for Robos, where it appears that virtually every option has some key advantage, and many of those options actually do.
Still, here's the best fitting and equipment for an ideal PvE Robo:
[Balanced], 4 points
Power Pool Increase
Team Boost Increase
Power Pool Return
[Engineer], 9 points
Repair Power Reduction
Repair Overcharge ->
Repair Arm Speed
Mace and Shield (dddddd)
HEL-TAC Rifle (pprddd)
Focused Repair Arm (rhhhhh)
Robotics Crescent Jetpack (pppppp)
Medical Station (hhxccc)
Power Station (xxnccc)
Personal Turret (rddddd)
Dome Shield (mmm)
Level 30 is assumed for skills, giving you the full 13 skill points. As you build up toward level 30, put your points into the Engineer skill tree first, then finish the Balanced tree with your last four. One of the big advantages of this build is that both stations and turrets use the Engineer skill tree, and as a result, you have lots of good options for your off-hand equipment later on. Every other class has to make tough choices; all of them will almost certainly be carrying an unbonused main weapon or off-hand. For Robos, your main weapon and all of your off-hands will be bonused. The melee weapon requires level 32; until then, the Heavy Wrench is a fine substitute. The Jetpack requires level 40; use a Hands Free jetpack until then.
One of the things that makes Robos so hard to play is that the key element of being a Robo is over-looked: you are a thin-skinned support character, the closest thing GA has to a Mage archetype. A good Medic will heal himself first, the Assault second, the Recon third, and the Robo last... if the Robo gets any healing at all. A competent Robo should be backing up the other characters, not demanding support himself. And yet, so many GA Robos play extremely aggressively, often at the forefront of attacks, rarely using their turrets, pets, or stations, and blasting away with the ridiculous short-range Robo shotgun. And then getting pissed on comms when they die because the Medic isn't healing them. This is not how you are supposed to play this class.
The correct way to play a Robo: your job is to ensure that the team holds the ground that the Assault takes. In short, your job as a Robo is to do everything you can to make sure the team isn't pushed back as it advances. Don't worry about getting a lot of kills or doing a lot of damage. Your Assault and Recon are the DPS characters. By playing a Robo incorrectly, a lot of bad Robos try to rack up kills with their gun. But the funny and Zen thing about playing a Robo correctly is that if you do it, you'll actually rack up just as many or more kills as the DPS characters. You're just doing it defensively instead of offensively. A correctly-played Robo shines in GA raids for this reason, since GA raids are defensive in nature.
With this in mind, start learning the PvE maps. In each of them, there are obvious choke-points or defensive strongholds. The game even hints at where they are by placing large clumps of enemies in front of these choke-points. The Assault and Medic will charge into these choke-points. Let them. The Recon will find someplace behind and above the Assault and Medic to snipe away from. Let him do that, too. Let them all draw the threat away from you. The team's advance will stop as the Assault and Recon apply DPS and the game's AI tries to dislodge them and push them back. Once that's done, you can move in. Find defensive cover near the Assault and Medic. This is where your Medical Station and Power Station go. This location will be behind a doorway, wall, or set of crates, tucked into a nearby alcove, over the ridge of a set of stairs, at the top of a ramp the Assault is firing down... as you gain experience, you'll learn the right spots for them. You don't want these stations drawing a lot of fire. Plant both of them, hit "3" to bring up your Repair Arm, then right-click your mouse and wave your mouse pointer back and forth over them to get them both up quickly. This is referred to in-game as a "nest."
Once that's done, cautiously turn the corner and expose yourself briefly. If the Assault is doing his job, you won't draw much, if any, fire. Plant the Personal Turret, bring the Repair Arm back up, and right-click to add some hit-points to it quickly. Then duck back behind cover near your Medical and Power Stations. The turret is planted properly if you can repair it and keep it repaired without exposing yourself too much. Do so, keeping your right mouse button held down and keep repairing that turret. It will draw a ton of fire almost immediately. The great thing about the Focused Repair Arm is that while you're holding down the right mouse button, not only does this focus maximum repairs on the turret, but it also increases the turret damage by 40%. This combination of infinite free healing, infinite free power, and infinite free DPS really makes the Robo class unbalanced compared with the others. When I'm playing a Robo, there are long stretches when I don't fire my gun at all and yet I can still run up a couple hundred thousand damage and get 40 or 50 kills with my turret alone.
There's a certain amount of disagreement about which turret is best. There are four options: the Personal Turret, the Autocannon, the Flame Turret, and the Rocket Launcher. In my opinion, there is no best option and a good Robo should have solid versions of all four in their inventory, because each has a key use. The Flame Turret is most useful for boss encounters in solo PvE missions. The Autocannon is fantastic in PvP, but is also useful in a couple of PvE missions because of its long range. The Rocket Launcher is practically required for raids thanks to its long range and splash damage. But the Personal Turret is probably, overall, the best PvE turret. It does 20% more damage than the Autocannon and has a 180 degree firing arc. Its range is rather sub-par, but given that you're going to be using it defensively, this really isn't much of a disadvantage, particularly since its cool-down timer is so short. The most useful thing about it is that it instantly switches from target to target as each dies, allowing it to quickly mop up targets that the Assault softens up.
And even if the Assault is inadvertently killed, you'll soon find your turret taking his place... and ensuring that the team is not pushed back just because you've temporarily lost a person.
Your defensive options are only increased by the morale boost Dome Shield. Robos should be using their morale boost most frequently of any GA class. The Dome Shield is a huge defensive plus, particularly when the group is facing large numbers of weaker enemies such as Minions and Alarm Responders. I can't count the number of times I've saved the entire team's life by dropping a Dome Shield at a critical moment and then planting a Healing Station inside of it. This is particularly true in PvE raids, where the Dome can be used to stopper up entrances and exits. This gives all of the DPS characters a safe place to hide from fire for a few seconds, and lets their Medics catch up and recharge. And in a chaotic melee, with this build, your turret should rack up DPS so quickly that it will often only be 15 or 20 seconds after your Dome Shield drops before you have another available to use. Use them early, use them often.
You're carrying a gun and a melee weapon, but it should be rare that you use either. The gun can be used as the team advances; since your turrets and stations are only useful when the team is stopped, you can fire away when the team is not stopped. Still, rather than worrying about damage, I prefer a gun with a power-saving mod so I can fire more or less continuously. It is for this reason that I don't use the Colony Energy Rifle with my Robo, either. I want to put a lot of shots out there. Your melee weapon is most useful against Elite Techros, whose version of the Rumbleblaster "ping-pong ball gun" is so incredibly annoying. The Mace and Shield includes a Power Sap bonus that quickly takes this weapon away from the Techros and makes them easier for the rest of the team to deal with.
I am not a particularly big fan of the Robo pet tree and the mechanical pets that go with it. All of them are both short range and very short duration. You're not helping your team nearly as much with these options. Similarly, the Force Wall can be extremely tempting to new Robos and indeed, it is an invaluable replacement for the Power Station in solo PvE missions. But longer term and particularly in Max security missions, the Force Wall is just not as helpful as the Power Station. Both the Assault and Medic need the extra recharge coming off a Power Station to operate effectively in higher level missions. You will catch a lot of hell if you're not carrying one.
Finally, when the boss fight comes, don't be afraid to strike off on your own a bit. In nine out of ten boss encounters, you should wait for the Assault to draw threat before even entering the room, then enter and go in the opposite direction of the Assault, whatever that was. Plant your Medical and Power Stations behind cover somewhere (call out "nest is up" on comms once that's done), then find a good place for your turret. By splitting threat from both the boss and any support, you're making life easier for the Assault/Medic team and making it more likely you'll get through the boss fight without anyone dying. Put up the Dome and the turret as soon as you can and you'll soon be rewarded with its cheerful little "phut-phut-phut" sound as it racks up DPS. ;-)
Whew! Long guide. Playing a Robo correctly in PvE is an exercise in tactics, not twitch. It's the class where you have to be most familiar with the maps and layouts and is therefore a very poor class choice for GA beginners. But a good, involved Robo in PvE will make the difference between a successful and unsuccessful mission; or will keep an unsuccessful mission or attack from turning into a rout.