Here is the full list of all 19 Obscure II Obscure: The Aftermath achievements. It takes around 6-8 hours to unlock all of the achievements on Windows.
Finish the game.
Obtain every available weapon during a game.
Open all of the chests.
Jedidiah won't make any more trouble.
Get to the main yard at Leafmore.
Prepare a serum, an improved serum and a powerful serum.
Find Sven.
Get to Jedidiah's house.
Consume 10 energy drinks.
Find Amy at the Fallcreek dam.
Go through the hospital.
Heal a teammate 10 times.
Find Jun.
Find Corey's car and get to the hospital.
Recharge electric weapons 10 times.
Meet up with Kenny and Amy at the Delta Theta Gamma party
Open a chest.
Go to the Delta Theta Gamma party.
Over-consumption of tea is not recommended.