Serious Co-Op

[RaYnE77]

i played through the game in co-op on serious difficulty with extra enemy strenth on 400% and the achievement did not unlock,
now no one else played i did this all allone, would that stop me from getting this achievement? and if not, why didnt the achievement unlock? anyone know or got any ideas?:confused:

[Bullett00th]

for me the achievements worked 50% of the time, but i don't really care about them and suggest you to do the same. its all about the game after all :)

[Dancing Muton]

Yes, it's because you were playing alone. Read the FAQ for more information.

[wretchx]

For serious co-op, do you have to complete the game in one sitting? Or can we go back to the level we stopped at?

[Redboy]

YES one sitting, need start till to the end at least with someone