Right, so for the Extinction noob among us (me being one of them). Is this gamemode any good, is the potential for a decent storyline available, has nightfall added anything to the gamemode? Does it feel like it has longevity, is it round based on boss round based (i.e. kill the boss and the game ends) or is the rounds unlimited just as in zombies. Do the waves of aliens just keep coming, do they have any "wonder" weapons.
How about the dialect from the characters, are they adding enough to the game, are they given you hints and tips on what should be done and where to find things and what to look for?
Overall, is it worth buying just for extinction? I do not care for mulltiplayer anymore.