First section

This section covers Yugi solving the Millennium Puzzle

Second section

This section covers Yugi's first encounter with Seto Kaiba from the manga

Third section

This section covers second encounter with Kaiba in Kaiba Land. It omits many areas that don't deal with the card game

Fourth section

The fourth section is an original story, occurring only in the novel. Two weeks after Yugi's battle with Kaiba in Kaiba Land, Yugi gets a call from Kaiba, who tells him to meet for a Duel at the top floor of the KaibaCorp. Yugi accepts, and when the duel begins, they use a special variation called the "Bingo Rule," which prevents the used of a specific card in each player's deck. Kaiba seems to be himself, but plays a different trump card, the "Automatic Giant".

Mokuba stumbles in on them, and tells Yugi that Kaiba has not yet awoken from his catatonic state. It turns out that the Kaiba that Yugi is playing against is a Cyber Kaiba, controlled by the KaibaCorp computer, and using all of Kaiba's memories.

Yugi defeats the "Automatic Giant" and Kaiba with a card called "The Unknown Egg".

(Source: Yu-Gi-Oh! Wiki