Cloverpit Endings + Sacred Charms

Steam Community guide by Brandon't.

First things first

Ensure that you have gotten all your drawer slots as you will need all the corpse pieces, drawer slots can be earned by reaching a certain deadline and once you have a key for that run, you cannot get another so this will take at least 3 runs.
Before beginning a run, if you want to guarantee that you start with all the corpse pieces (excluding the skull as this is found randomly in the shop) make sure that when you end a run that you have all your drawers filled, as this will transform those items into corpse pieces on the following run.
Below is an image showing that last run there were two trinkets in the bottom two drawers, therefore I will be able to start with 2/4 corpse pieces.

It is possible to gain corpse pieces during a run but I'm not sure what the criteria is for this and it's not too bad of a debt increase from the beginning so it's best to just start with all 4.
If your drawers are empty, a good way to easily fill them before starting a corpse run is to use the "Cold Affection" memory card, buy 4 things and then just hit restart.
The skull should be easy enough to find as it's only a common rarity item, even better if it has a modifier!
That's all you really need setup for either of the two endings.

Obtaining the bad ending

For the bad ending, it's as simple as playing through the game and reaching the 250k coin quota (or 500k with Delusions of grandeur memory card) where beating this quota will unlock the dark key and allow you to leave through the exit behind you.
Doing so will award you with the credits and will give the memory card you used a rainbow border effect (not fully holographic yet) but this is the bad ending and we can do better.

Obtaining the good ending (+ sacred trinkets)

For this ending I recommend that you use the 'Heartbreak' memory card to guarantee that you get at least one 666 as you will need to roll one at least once, more on this further down.

In order to transform the phone and get the good ending you must not take any phone calls that contain red text and a lower pitched voice.

You are allowed to take from these calls or ignore them if you want, doesn't matter

You CANNOT take from these calls

Opening the menu is fine, just hit "Be right back" and don't come back.
Once you finish a deadline that had a red phone call, you will get one mark on your 666 floppy disk. You just need to do this 3 times, then after the 3 mark is gained, just take one more phone call and the phone will transform!
In order to get all three strikes you will need to obtain at least one '666' pattern as doing so will force your next phone call to be red, if you do not do this then you will only get 2 red phone calls by deadline 8 as the other two are guaranteed on deadline 3 & 7.
After you have 3 strikes on your 666 floppy disk, your next call will be holy and will transform not only the phone into holy calls (Where you can get sacred charms) but will also transform the key which when used on the door will give you the true ending.