Mark of the Demon

First, identify which role cards everyone has at the end of the game and answer the corresponding question on the game board. You may not always be able to see the cards, but the players' behavior can help you figure out which is which. Each game board question begins "number the xth", which indicates a letter in that question's answer. Turn that letter into a number using use A=1 Z=26.

Next, find a name for each role. These are nicknames given to the players in other real VHS board games. Find the name of those games, and use the number from the first step to index into it and get the answer to Part 1.

To help identify the games, consult the DarkGrimoires.txt file, which gives word lengths for all of their titles. If you get stuck, here is the list of games: (see next hint)

The games you're looking for are
Atmosfear: Khufu the Mummy
Nightmare
Nightmare III: Witch
Nightmare IV: Vampire
Star Trek: The Next Generation – Interactive VCR Board Game – A Klingon Challenge
Star Wars: The Interactive Video Board Game: Assault on the Death Star
Video Grin N' Bear It
Waynes World VCR Board Game

Look for letters appearing over the video at 1:09. It’s easier to catch them if you go frame by frame.

TNG SHIP SUFFIX

Reverse the reversed audio at 2:36 to hear a clue.

DONUT SHAPE

The solve path for the maze at 2:34 draws the letter N.

The white bands of static at 3:47 are Morse. Decode them top to bottom, first screen to last.

The static decodes to DIMPLED BALL GOES HERE.

The audio stutter in the line "I must say, I will miss our little games" at 4:10 gives you the letter R.

The stacked lines in the “Please Stand By” graphics at 4:37 encodes semaphore.

The Stand By semaphore spells out MDMA.

The image at http://bit.ly/SpookyScaryHiddenURL will need to be desaturated in an image editor.

TWO VS KISSING

The chirping audio at 6:40 needs to be played into an SSTV decoder like RX-SSTV, specifically using Marlin 1 mode. You can get RX-SSTV at https://www.qsl.net/on6mu/rxsstv.htm

A picture of an EYE.

The insect sounds at 8:08 are bug sounds from Animal Crossing (2001) aka Animal Forest. Index the number of times the sound is repeated into the name of each bug to get the cluephrase.

FOURTEEN

The tops of each character column at 10:11 are Pigpen characters

LOOK AT ME IM SANDRA

The image that flashes for a frame at 11:51 says DIAL FOR MURDER

Convert the numbers on screen at 12:24 from ascii → base 64 → hex → text

ROT THIRTEEN R

Scan the QR code in the demon face at 13:08 to get MOVIE BUT EVERY TIME THEY SAY.

Turn on closed captions on the video while the voiceover is playing at 14:24.

OHM MEASURE

To decrypt the phrase at 15:24, shift each letter right one space on a QWERTY keyboard

COMMON BLOOD

Each of the mini-puzzles in the video gives you either a letter, or a cluephrase whose answer is a letter. Arrange them in the order they appear in the video to get your answer. For complete spoilers, here are full list of clues and solutions: (see next hint)

TNG SHIP SUFFIX = D
DONUT SHAPE = O
maze solution = N
DIMPLED BALL GOES HERE = T
audio glitch phoneme = R
MDMA = E
TWO VS KISSING = W
eye image = I
FOURTEEN = N
LOOK AT ME IM SANDRA = D
DIAL FOR MURDER = M
ROT THIRTEEN R = E
MOVIE BUT EVERY TIME THEY SAY = B
OHM MEASURE = R
COMMON BLOOD = O