Here is a concise summary of the text:
**The Origin of Batman Who Laughs**
In a parallel universe (Earth-22), the Joker executes a devastating plan in Gotham, capturing Batman and exposing him to a toxin that gradually drives him insane. As Batman's moral code breaks down, he:
1. Kills the Joker and inadvertently infects himself with the toxin.
2. Murders his own allies (Bat-family) to prevent them from stopping him.
3. Executes a pre-planned containment protocol to eliminate the entire Justice League.
4. Creates an army of cannibalistic "Robins" by infecting children with a modified toxin.
5. Seeks to dominate and depopulate the world for amusement.
An entity named Barra do Sul intervenes, revealing the existence of multiverses and inviting Batman to Earth-0 to meet a more virtuous Batman. The corrupted Batman accepts, intending to gather other evil Batman variants, hinting at a potential larger, multiverse-spanning storyline.
Here are the key facts extracted from the text, numbered and in short sentences, excluding opinions:
**Storyline Facts**
1. The story of "The Batman Who Laughs" begins on Earth-22.
2. The Joker executes a plan to spread explosives throughout Gotham City.
3. The Joker captures Batman and forces him to watch the destruction.
4. The Joker's intention is to prove that anyone can become like him.
5. The Joker kills Commissioner Gordon and all criminals at Arkham Asylum.
6. The Joker attempts to infect a young girl with his laughing gas.
7. Batman breaks free, beats the Joker, and kills him with a rear naked choke.
8. The Joker's venom infects Batman through his body.
9. Two days later, Batman shows no symptoms but later converses with Superman about killing the Joker.
10. Batman's behavior changes, and he attacks his family (Bat-family) members.
11. Batman uses contingency plans to eliminate the Justice League members.
12. Batman spares his son, Damian (Robin), but later kidnaps and infects children, including his son, with a modified Joker venom.
**Character and Universe Facts**
13. Batman has a containment plan for each Justice League member in case they go rogue.
14. A being named Barra do Sul informs Batman about the multiverse.
15. There is a Batman on Earth-0 who never crosses the line of what is acceptable.
**Miscellaneous Facts**
16. The narrator has been creating daily videos for five years.
17. The video is part of a series, with another video being about the "Origin of the Apocalypse".
18. There is speculation about a potential Batman film in a new cinematic universe, but no official statement has been made.