Play Freeplay Mode on the Security Tower map with 1-on-1 settings (Team Size should be set to 1, as should Max Team Size). Start as a Resistance member of the Soldier class and blow the door to access the next mission objective, then change to the Operative class. Go toward the safe you are supposed to hack, making sure not to be killed by the security agent. When that security agent/engineer tries to remove your hack box, position yourself on the opposite side of the glass. If positioned properly, your adversary will spray ineffectively and you will gain experience due to the "hacking" and "guarding" functions you are performing. As long as you aren't positioned too close to the safe, you'll be stuck in a stalemate with your opponent and will earn experience the entire time. Then, when you're ready, move closer to the safe to complete the mission and receive your points.
Switch to a heavy body type, then choose a gun of any weight and customize is as desired. Do the same thing for your secondary weapon. Make it your default weapon and switch back to a light or medium body type. Your default guns will remain the same, but your body will not. When you play matches, you can mow have a light or medium body type with a Gatling gun.
ACHIEVEMENT - HOW TO UNLOCK 'Tis better to give than receive - As a Medic, using the Transfer Supplies ability, give the last of your Supplies away. A bit of a headache - Take down an enemy with a Cortex Bomb. Boom! - Detonate a HE Charge. Brinksmanship - Complete an Operative Primary Objective within 5 seconds of breaking disguise. Cut 'em off at the pass - Close an enemy team's shortcut. Great shot kid! One in a million - Take down an enemy by shooting a grenade. I live... again! - Revive yourself. I think I know a shortcut - Open a shortcut for your team. It's a trap! - Take down an enemy with a Satchel Charge. King of the world! - Complete all 3 Star Challenges. No I insist, you take it - Use the last of your Supplies to refill a teammate's ammo rather than your own. Not over till the fat lady sings! - Take down an enemy with gunfire while knocked down. Not so sneaky now, are you? - Reveal an enemy in disguise. Oh I'm sorry, was that yours? - Capture an enemy's Command Post. Pump up the volume! - Upgrade your team's command post. Smart decisions win battles - Attempt to Revive an objective-class teammate over a non-objective teammate near a Primary Objective. That mine you found? Disarmed! - Spot a mine which is later defused by another Engineer. That's how you win a match - While on defense, take down an attacker who's completing a Primary Objective. The start of something big - Win any mission, whether campaign or What-If. The story has just begun - Win both story campaigns (not including What-If missions). They never knew what hit them - While on offense, win the match in less than 30% of the time limit.. Time to start a new character - Reach rank 5. To serve and protect - Win every Security campaign mission, including What-If missions. Tough as nails - Win all storyline campaign missions (not including What-If missions) playing either Online Versus, or in Hard mode. Use the wheel, earn more XP - Complete an objective after first selecting it on the Objective Wheel. Very well done indeed! - Complete your first 3 Star Challenge. Viva la revolution! - Win every Resistance campaign mission, including What-If missions. Was it the red or the blue wire? - Disarm an HE charge. Well done! - Complete your first 1 Star Challenge. Well that was educational - Collect all Audio Logs. Who's bad? - Complete all 1 Star Challenges. You can place another mine now - Take down an enemy with a mine. You shall not pass! - While on defense, prevent the attackers from completing their first objective. You're going places, kid! - Reach rank 2. You've escaped the Ark - Win all main missions of the Resistance campaign (not including What-If missions). You've saved the Ark - Win all main missions of the Security campaign (not including What-If missions).
"Agents Of Change" achievements A Burning Thing - Kill an enemy with a Napalm Grenade. Ark King - Reach level 24. Mutual Support - Have a Field Regen Unit buff more than 3 players simultaneously. Pyromancer - Kill an enemy with a Pyro Mine. Remote Control - Kill an enemy with a UAV. Science Maven - Win Labs as both factions in Campaign Mode. Towering Achievement - Win Founders' Tower as both factions in Campaign Mode.
To use a heavy gun with a small body type, change to a heavy body type and select a gun (make sure it's exactly how you want it as you cannot edit it afterward). Choose any gun of any weight. Now, do the same for your secondary and make your default weapon. Go change back into a medium/light body type. Your default guns will stay the same, but your body will not, thus, when you play matches, you can have a light body type with a gatling gun.