There are quite a lot of collectibles scattered through out the levels in Until Dawn and they're easy enough to miss as it is, but can the choices I make cause me to miss any of them? Am I able to get them all of the collectibles in one go, or will I have to play multiple times? I feel as though with the amount of choices available, there has to be a decent amount of missables if I make the "wrong" choice.
The short answer is that there are collectibles that you can miss depending on your choices, but you can get them all in one playthrough. Below is a list of such collectibles:
Missable Set 1: Mystery Man Clues # 24 - 30
Obtained in: Chapter 7 as Sam
Related Butterfly Effects: Rats with bushy tails, Something for later, Run or hide.
How to Obtain:
Sam must escape the Psycho in Chapter 5. This requires Chris to have not shot the squirrel in Chapter 1. Additionally, Sam must make all the right choices during the chase. While there are multiple ways to escape, the idea is to simply run into the basement until you get to the wooden door whose knob is on the shelf. Once you get through the door, you must hide in the elevator shaft. If Chris shot the squirrel, Sam would have a wound on her forehead. which would reopen during the chase and give her position away. If the baseball bat is accessible in the basement (via Something for later), she can hide in the basement and use the bat to defend herself, but she will then end up at the same wooden door above.
Missable Set 2: 1952 Clue # 17
Obtained in: Chapter 8 as Emily
Related Butterfly Effects: None.
How to Obtain:
Emily must successfully avoid and hide from the man with the flamethrower at the end of Chapter 7. This can done by succeeding all the Don't Move and QTEs when you encounter him and hiding once you reach the dead end. Failure to evade him will result in the loss of this collectible, but note that if he finds you hiding, you will be able to get the collectible.
Missable Set 3: Loss Totem # 5
Obtained in: Chapter 9 as Ashley
Related Butterfly Effects: Left behind.
How to Obtain:
Ashley must investigate the voice instead of catching up with the rest at the crossroads. All instincts will tell you to stick with the group and with good reason: Ashley has the potential to die after making this choice. All hope is not lost, however, as you just have to avoid the rattling trap door to keep Ashley alive. Just make sure you grab the totem before walking by the trap door and you will meet up with the rest of the group shortly thereafter.
Missable Set 4: Loss Totem #6
Obtained in: Chapter 10 as Matt or Jessica
Related Butterfly Effects: To the rescue, On the same page, In self defense, Who gets the gun, Save yourself.
How to Obtain:
Either Matt or Jessica must survive to Chapter 10 in order to get this collectible. These characters are probably the easiest to lose in the game: Jessica because she can die as a direct result of Mike's actions and Matt because there are so many ways he can die. To save Jessica, you must take all of the quick or risky options when Mike is chasing her in Chapter 4. If she is still moving when you get to her in the mines, then she will survive to Chapter 10. Matt is a little more difficult. Firstly, he should not attack the deer in the beginning of Chapter 6. If he does, they will force him off the cliff and will fall to his death. Later in the chapter when you get to the radio tower as Emily, things get a little more complicated as his survival depends on three different choices: did he agree with Emily to go to the fire tower?, did Emily give him the flare gun?, and did he jump to safety instead of helping Emily? If you try and help Emily twice and Matt does not have the flare gun, he will die. How do you give Matt the flare gun? Emily must give it to him, but he will fire it into the air immediately if he agreed with Emily about going to the fire tower. Therefore, if you want to help Emily twice, Matt must disagree about going to the fire tower and then be given the flare gun. Another option is to have Matt save himself. Emily will hate him for it, but Matt will survive without the need of the flare gun.
Please note that these are collectibles which are missable as a result of choices; you can miss many more, including these, if you fail to explore an area before moving on. To minimize your chances of missing a collectible this way, always walk away from where the camera is leading you first as many collectibles are hidden this way.