This is a possible summary of the user's message:
Markiplier plays The Somewhat-Impossible Markiplier Quiz, a fan-made game that tests his knowledge and memory of his own videos and experiences. He answers questions about his name, his career, his games, his fears, his dog, his fans and more. He also reacts to clips from his past videos and gets emotional about how far he has come and how much he appreciates the community. He fails many times and rages at the game, but also laughs and enjoys the nostalgia. He thanks the creator of the game and encourages his fans to make more things for him to see. He ends the video with his signature outro.
Here are the key facts extracted from the text:
1. Markiplier's real name is Mark Edward Fischbach.
2. Markiplier's birthday was the reason he played "The Somewhat-Impossible Markiplier Quiz".
3. Nicholas Lovett created the quiz game as his first flash animation project.
4. Nicholas Lovett is an 18-year-old fan of Markiplier's who has been watching his videos since Amnesia.
5. Markiplier's greatest hero is his dad.
6. Markiplier's first video was the Amnesia Reaction Compilation.
7. The phrase "WHERE'S THE BLACKSMITH???" originated from Markiplier's mouth.
8. Markiplier has a horror playlist on YouTube with an unknown number of videos.
9. Markiplier's dog is named Buddi (later discovered to be a girl).
10. Markiplier was born on a military base, possibly in Hawaii.
11. Markiplier had most fun playing games other than Vanish.
12. Markiplier played and recorded the most of Prop Hunt in GMod.
13. The setting of the first episode of Octodad: Dadliest Catch was a wedding.
14. Markiplier has always wanted to go to space.
15. Markiplier became emotional while playing Dreadhalls and cried a little.
16. Markiplier's favorite subject to teach would be American History.
17. Tiny Box Tim is Markiplier's "Little Biscuit".
18. In Vanish, everything made Mark jump.
19. Markiplier got a question wrong and failed the quiz during his first playthrough of The Impossible Quiz.
20. Markiplier raged the most on the Double Kidney operation in Surgeon Simulator.
21. Markiplier has been doing YouTube for almost 2.5 years at the time of recording.
22. Markiplier loves being reminded of the things he's played in the past and making new memories.
Note that these facts are based on the text and may not be entirely accurate or up-to-date.