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