Overview
-Estimated achievement difficulty: 4/10
-Offline: 11 achievements for 170 + 3 for 50in DLC
-Online: 1 for 30
-Approximate amount of time to 200 : 10-15hrs
-Minimum number of playthroughs needed: 1 per game mode + Repeats to finish leveling
-Number of missable achievements: None. Repeatable missions
-Do cheat codes disable achievements?: No cheats
-Does difficulty affect achievements?: No.
-Glitchy achievements: None
-Unobtainable achievements: None
-Extra equipment needed?: None
Introduction
Zombies! A zombie outbreak has sent your home island into a panic and you must fight with some new found friends to survive, and make your way off the island. You and your fellow zombie soldiers must destroy the zombie hordes to help save their fellow survives, and also secure a way off of the island. Whether or not any of you will ever make it off the island is unclear, but you'll certainly pwn many zombies in the process.
Story Mode
In order to unlock Blackout and Survival mode, you will need to play through every level in story mode. The first achievement you will most likely get in story mode comes naturally; "The Law is Dead", but most the rest require some added effort on your part. During this time you will want to try and get $20,000 in a single chapter for "Money Grubber", complete the story alone for "Alone at the End", do all objectives in each chapter for "Hard Worker" (1 chapter) and "Exhausted" (all chapters), as well as level each character as much as possible for "Playing With Power". You may also want to rotate your characters regularly so you can use their pwnage ability at least 10 times each for "Got Pwnage?".
Co-op
You will need to do the entire story mode, via New Game, with 3 other people to get "Epic Run".
Blackout Mode
Blackout is a survival mode in pitch black outside of the area immediately surrounding you. It's not quite as bad as it sounds if you play with the AI, who still have no problem shooting zombies in the darkness. In this mode you will need to survive for at least 15 days, after which you can feel free to fail and get sent back to the menu.
Survival: Classic
Another wave-based game mode, and this time around you must survive for a total of 30 days. At least you can see, and overall it's really not too difficult compared to either blackout or story mode.
Prequel: Day 56 (DLC)
Zombie Apocalypse 1 veterans should recognize the characters you play in this single level mode. It is more or less a wave based game mode consisting of about 8 waves, and you will see every enemy during the duration of the mode. This mode more or less acts as a segway from the first game, into the second one.
Pure Pwnage Mode (DLC)
This mode takes place on the same map as Prequel: Day 56 and pits Jeremy and his friend Doug against hordes of zombies. I personally feel Jeremy is the best character in the game, and Doug has the same skillset, so this mode is just pure fun. You can get two achievements here, one for lasting a total of 10minutes without failing ("Warm it Up") and the other for killing a total of 10,000 zombies, cumulatively, in this mode.
[x360a would like to thank Shiftie for this Roadmap]