Unique Boss weapons
Successfully complete the indicated task to unlock the corresponding unique Boss weapon and its blueprint:
Flycatcher's P90 (SMG): Successfully complete the "Flycatcher" mission. It has high damage and mag capacity, punishing recoil, low accuracy.
Rosebud's Zastava M93 (sniper): Defeat the elite sniper in the "Rosebud" mission. It has the highest penetration in class, high damage, tough to control.
Sharp Thunder (pistol): Defeat Walker at the end of the story to unlock his signature Revolver. It is highly stable with a huge kick. It usually is a one-hit kill on most enemies, no matter where you shoot them on their body.
Silver Stake Tactical (assault rifle): Defeat Walker at the end of the story to unlock his signature ASR. It is a tactical variant: integrally suppressed and highly accurate.
Silverback's KSG12 (shotgun): Successfully complete the "Silverback" mission. It has the largest magazine in class at the cost of range and reload speed.
Unlock the following three skills/perks as soon as possible to make leveling much easier. Only one of these perks needs to be equipped to your character. The other two are passives -- so you will instantly earn more XP at the start of the game.
Experience Upgrade (Passive): +20% XP bonus.
Pistolero (Perk): +40% XP bonus while using a handgun.
Recon Master (Passive): +50 XP when marking enemies with your drone.
Bonus: At any camps, select "Research" Preparations for +10% XP for +1 hour.
These three perks all include bonus XP rewards. The Experience Upgrade perk is found in the "Basic" circle, the Pistolero perk is in the connecting "Weapons" circle, and Recon Master is in the "Recon" circle. Once you unlock two skills in the "Basic" circle, these two new skill circles will become available. This build is basically stealth-focused and gives you large bonuses for using silenced pistols and marking enemies with drones. To get additional XP, try selecting the Panther class. Silencers do not decrease damage with pistols/SMGs, and you will want the Slim Shadow perk, which gives you a +80% bonus to stealth and vanish. That makes getting close a lot easier. For drones, try using the Drone Mark Area upgrade from the "Skills" menu. This increases the area-of-effect for drone marking by +75%. As you reach new areas, you will encounter increasingly large groups of enemies. This makes marking them with your drone a lot easier and quicker. Combine these perks, including the +10% XP camp bonus, to earn +70% XP for every pistol kill, +65 XP for marking enemies, and +30% XP for everything else.
Accomplish the indicated achievement to get the corresponding number of Gamerscore points:
A safe haven (15 points): Reach the end of Act 1.
End of Act 2 (15 points): Reach the end of Act 2.
End of Act 3 (25 points): Reach the end of Act 3.
Breakpoint (90 points): Reach the end of Act 4.
Totsiens! (15 points): Finish A GREAT ESCAPE.
Cry Wolves (15 points): Finish SPEAK NO EVIL, HEAR NO EVIL, SEE NO EVIL.
You can't stop us, Nomad! (15 points): Finish FRIENDLY FIRE.
Change hurts (15 points): Finish POINT OF NO RETURN.
Here's your World 2.0 (25 points): Kill Walker.
Tell your story (15 points): Complete the optional dialog in Erewhon about your past.
Absolute Mastery (90 points): Reach Rank 10 with any class.
In the belly of the beast (15 points): Enter the raid.
Born in the purple (15 points): Wear all High-end or better equipment.
Lord of War (15 points): Equip a legendary weapon.
Two-faced (15 points): Unlock 2 Classes.
Four Honor (15 points): Unlock 4 Classes.
Jack of all Guns (25 points): Kill an enemy with a handgun, an assault rifle, a sniper rifle, a DMR, a shotgun, an SMG and an LMG.
This one is mine (25 points): Upgrade a weapon to Mark 3.
Prolific gunsmith (15 points): Upgrade 20 weapon intermarks in total.
A hero of our time (15 points): Reach Level 30.
Wildland Millionaire (15 points): Spend [50.000] eSkreds.
Attachments Master (15 points): Find  Attachments and then equip one in the gunsmith.
Executive perks (25 points): Unlock  Aptitudes in the skill tree.
Drone farmer (15 points): Destroy 50 enemy drones.
It's free real estate (15 points): Discover  different Bivouacs.
Expert Herbalist (15 points): Pick up  different natural resources.
A Man of the World (15 points): Discover  different Provinces.
The woe of wit (15 points): Find  clues in the world.
Heart of Darkness (15 points): Find 100 Wild Mysteries.
Master Craftsman (25 points): Find  Blueprints and then buy 5 Weapons on Demand at Maria's.
David's Challenge (25 points): Kill a Behemoth.
Hunter becomes the Hunted (25 points): Kill  Wolves.
Swiss Army Killer (25 points): Kill an enemy in Ghost War as the Panther, Assault, Medic and Sharpshooter.
War never ends (15 points): Finish 8 Guerilla Missions in a single day.
Elite Guerrilla (15 points): Finish  Elite Guerilla Missions.
Entry-level combat (15 points): Win 1 Match in PVP.
Squad Goals (15 points): Finish 3 missions in Coop.
Synchronized and deadly (15 points): Kill an enemy 1 second after another player in Coop has injured him.
What a maniac (15 points): Kill  enemies by running them over.
The night is dark (15 points): Kill 12 enemies without getting detected.
Snapping turtle (15 points): Kill an enemy with CQC from prone blending.
Simple Geometry (15 points): Kill 2 enemies with a single rocket.
You Monster (15 points): Destroy a Farmer drone.
Sting like a bee (25 points): Kill a Breacher, a Rocket Gunner and a Sniper with CQC while in stealth.
A brutal stop (15 points): Kill a convoy's driver with a sync shot drone.
Bang bang (15 points): Get 3 headshots with a handgun in 5 seconds.
Bird watching (15 points): Kill a helicopter's pilot with a sniper rifle or DMR.
Expert Marksman (15 points): Kill 2 enemies more than 200m away with headshots in 3 seconds.
Death from above (15 points): Kill an enemy 5 seconds after landing from a base jump.
Get it off me! (15 points): Shoot a wasp while it is still on it's carrier's back.