Things I wish I knew Before attempting 100% achievements.

I will do my beast to keep spoilers out of this guide, to that order i will give you the name of the achievements and the description, as they are no hidden achievements in this game, so you can read them from the achievements section on steam.

This will likely be the last achievement you will get, but it comes with the earliest game bug that will make it impossible to get. The PP trial “Drinking To Create”, requires you to create the Beer Hat combo weapon 50 times. The blueprints for this combo is not found in the world map as a collectible, but rather you unlock it when you purchase the second level of the Smarts Attribute, In the Player tab of the Survival Guide. There is a glitch that seems to trigger if you purchase more than one attribute when you unlock the second level, that will make it so you do not get the blueprints, and in that way you will be unable to make the combo weapon and complete the requirements to get Prestige Hound. The solution seems to be to save the game manually before purchasing level 2 Smarts, leave the pause menu once you only purchased the attribute, then open the Survival Guide again, to check if the blueprints for the beer hat have been unlocked in the weapon blueprints tab. If it does not then load the save file, and try again. I had the displeasure to only realize i had this glitch when I had already beat the main story.

The steam version comes with the DLC The Untold Stories, each episode has their own set of unique collectibles that have their respective achievements In the case of episode 4, there seems to be at least 2 glitches involving the collectibles. The collectibles should only appear in the map and be able to be collected after reaching a specific point in the story, however it seems that if you load a saved game, the collectibles will show in the map regardless of story progress, and one of the Bootleg Zombrex will be noncollectable, leaving you at 19 out of 20. To avoid this, you play the episode from the start without loading a save file (which will require not dying or failing an objective) and get all collectibles the moment they are available at their respective points in the story. Also there seems to be a different glitch that may or not be related to loading a save file, in with three of the Biohazards will not count as burned, leaving you at 37 out of 40. If you do happen to run into this predicament, you can copy your save file folder to a different a different folder in your computer, disable Steam Cloud Saves for the Dead Rising 3, reset progress inside the game, play episode 4 in this brand new save file, from level 0 since the episodes carry your character progression form the main story and vice versa, get the collectibles in one sitting without loading a save file, once you to unlock this two achievements, you delete the save file folder for Dead Rising 3, copy back your save file folder that you kept separate, enable back Steam Cloud Saves, and you will keep your progress towards other achievements, though you will not be able to get all the collectibles in episode 4 in your save file.

This is the only multiplayer achievement in the game, I did not had any problem with this achievement, however, it was the first one i decided to get before dedicating my time to do 100% achievements Thankfully it seems like people still play the game with the co-op join in function enabled, so you should be able to get the achievement with relative ease. Also you don't need to do any missions or progression while in Co-op, just successfully joining will get the achievement to unlock in a few moments.

Besides this glitches and the need to join a Co-op game, the only thing stopping you from getting all achievements, is the fact that you will need to kill at least 340,000 zombies to get a some of he PP trials. Hence why “Prestige Hound” will likely be the last achievement to unlock, on the good side unlike previous Dead Rising games, you don't need to do this in a single run of the game, as the progression for the PP trials carries over between play troughs of both the main game and the DLC episodes.

Hopefully this will help at least one fellow completionist out there from having to start the game from zero, after realizing that some achievements have become unlockable just after you finish your first run of the game. Good hunting.