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.
Jedidiah won't make any more trouble.
Get to the main yard at Leafmore.
Find Sven.
Consume 10 energy drinks.
Get to Jedidiah's house.
Recharge electric weapons 10 times.
Find Amy at the Fallcreek dam.
Go through the hospital.
Open a chest.
Find Jun.
Find Corey's car and get to the hospital.
Meet up with Kenny and Amy at the Delta Theta Gamma party
Go to the Delta Theta Gamma party.
Over-consumption of tea is not recommended.
Open all of the chests.
Prepare a serum, an improved serum and a powerful serum.
Heal a teammate 10 times.