Diary of a Mad Man was a promotional magazine entry written for Cube Magazine in 2003. Written when "Hallucination" seemed to be the final iteration of Resident Evil 4, it is a summary of events leading up to the game.
Content
Diary
4 Months in 1 Day
"4 Months in 1 Day" is a timeline that extends from p.030 to the next page. The first entry is simply a summary of Resident Evil 2 (identified as "30 SEPT '98"). In Mid-October, Sherry has been placed in government custody owing to her G infection; Leon agrees to join an "underground anti-Umbrella organization". By Mid-November, Leon has begun his investigation; he contacts Claire and finds she is making progress with her own investigation (referring to her infiltration on the Paris lab in CODE: Veronica). When Claire contacted Leon at the end of December asking for help, Leon notified Chris who had to abandon his own Umbrella investigation (referring to his Europe trip referenced in Resident Evil 2) to come save her. By January 1999, Leon has collected enough information from Umbrella to begin his investigation.
An Umbrella History
"An Umbrella History" is Leon's summary of the viral incidents based on the information he has obtained. Spreading from p.032 to the next page, it is a summary of five games set in 1998 that had already been released. While Leon has met Chris and Jill, and knows about Jill's ordeal with the Nemesis (though incorrectly identifying the Nemesis as being infected with the "NE-T Virus", rather than having the NE-Alpha parasite in its body), he makes no mention whatsoever of Resident Evil Survivor, when he sent his friend Ark Thompson to investigate the company.
Monsters Everywhere
The "Monsters Everywhere" section starts on p.034 of that issue, and continues on to the next page. It lists the various viruses known as of 2003. The G-Virus entry is split in two, separating the primitive version Lisa Trevor was infected with from William Birkin's completed sample, which allowed him to implant embryos into other people's bodies. The t-Veronica Virus entry is significantly flawed; the section title misidentifies it as "T-VIRUS", and shows a picture of the Nemesis-T Type to go with it. The t+G Virus (referred to as TG-VIRUS) is described as having the powers of both, with the benefit of having an "electromagnetic shield".