Here is the full list of all 49 Trepang2 achievements.
Kill an enemy with a flashbang impact
Acquire all weapon parts
Complete all campaign and side missions on Extreme difficulty or higher
Collect all intel docs
106 is reborn
Collect 50% of all intel docs
Complete all campaign and side missions on Very Hard difficulty or higher
Kill all TF27 soldiers in Site 14
Throw a TF27 soldier into the helicopter blades in Site 14
Throw an enemy into the vent in the first combat encounter in Site 14
Use every bullet in a pistol magazine to get headshot kills
Eviscerate Dr. Emerson’s corpse
Let the world know
Break The Cycle
Cycle 106 comes to an end
Completed Level: Horizon HQ
Complete all campaign and side missions on Hard difficulty or higher
Kill the Horizon CEO
Kill an enemy with a tomahawk
Complete Level: Oil Rig
Shoot an enemy while he’s thrown as a hostage grenade, detonating his grenade
Complete Level: Crash Site
Shoot an enemy’s thrown grenade, killing him with it
Complete Level: Kellington Colliery
Complete Level: Site 32
Complete Level: Site 83
Stealth kill an entire squad without anyone becoming alerted
Complete Level: Iron Dragon Data Center
Complete Level: Jorvik Castle
Kill the Patriarch
Destroy 1000 cultist books
Acquire the dual wield serum
Slide into an enemy and grab him while he’s ragdolled
Kill an enemy with a headshot on final bullet in the mag
Complete Level: Gunnarson Complex
Kill an enemy by shooting through his helmet with a DMR
Complete Level: Pandora Institute
Kill the Mothman
Collect the Syndicate coin “XCV”
Alert an enemy by shining a flashlight from behind, shoot him before he turns around
Grab an enemy, throw and kill him with a headshot
Destroy 100 beer/wine bottles
Escape from Site 14
Kill a heavy soldier
Use a weapon bench to customize a weapon for the first time
Kill 3 enemies with 1 grenade
Collect the Syndicate coin “CV”
Execute your first hostage
Complete all campaign and side missions on Rage Mode difficulty