Advanced PET

The Advanced PET (アドバンスドペット) is a PET model introduced in Mega Man Battle Network 4 and used up to the 34th episode of the MegaMan NT Warrior Axess anime series. It was used to combat Nebula and the Darkloids, as well as competing in the Red Sun and Blue Moon Tournaments.

Description
This PET model looks much like a flip phone, the top has transparent glass so that even when closed the user can still see the screen. A sliding piece on the bottom causes the top to open, revealing the screen and buttons. Along the top of the device is a slot for Battle Chips, on the right side is a grip and on the left is a headphone jack. On the bottom underneath the slider is a port for charging. Unlike its predecessor, the Advanced PET comes in a wide variety of colors, and the NetNavi mark on the front can be customized as well. This PET introduced the concept of wirelessly jacking-in, which has been used in all PETs since. It is about 4 inches in length.

In the Games
Lan Hikari gets this PET sometime before Mega Man Battle Network 4. Lan makes no mention of it in game (although a message board post mentions that Dr. Hikari and Mr. Famous designed it). New features include the Emotion Window, and changes in the Navi Customizer. The interface is mostly the same as in Mega Man Battle Network 3 with color palette changes. The Japanese exclusive Battle Chip Gate toy could also be used to send Battle Chips to MegaMan in real time during a battle, even if the Battle Chip isn't in Lan's Folder.

In the Anime
Introduced in MegaMan NT Warrior Axess, but first mentioned in episode 55 of MegaMan NT Warrior. The Advanced PET was made by IPC (Blaze Quest in the Dub) and was completed with the aid of Chaud and ProtoMan. This PET uses a Route-Mate Molecular 450 GHz processor which was long thought to be impossible. The Advanced PET became immensely popular in very little time with commercials for its still running up to episode 30. Pressing the Navi mark will shine a laser used to Jack-In. Unlike the games the interface is completely re-worked. In episode 34 Lan’s PET is heavily damaged and is replaced with the Advanced PET II in episode 36. Advanced PETs are still used in some episodes of Rockman.EXE Stream.

In the MegaMan NT Warrior Manga
Lan gets the Advanced PET in Volume 7 and uses it until he gets the Progress PET in Volume 9.

Advanced PET II
A redesign of this Advanced PET was produced in a cooperation between IPC and SiLab. Only one model was ever manufactured. In episode 29 of the Axess series the PET was first revealed with the purpose of preventing the use of Dark Chips. Later in episode 36, the PET was completed and given to Lan after his was damaged in a fight. While it is not known if the PET can prevent dark chips from being used, the Cross Fusion abilities of its user is greatly increased. Lan continues to use this PET until he is given the Progress PET in episode 3 of Stream. This PET was used only in the spin off game Rockman.EXE 4.5 Real Operation, and is used by the player to control up to 21 net navis.

Toys
Electronic toy versions of the Advanced PET have been distributed to the Japanese and American market by Takara and Mattel. Various toy Battle Chips are also distributed for use on the PETs. The PETs simulate housing a virtual NetNavi that can battle with fictional computer viruses or other NetNavis, similar to digital pets. Only the Advanced PET has been imported to the United States market and other countries. This version uses physical Battle Chips to fight "viruses," and two can be connected with a link cable. The Advanced PET comes in three different colors (MegaMan, ProtoMan and Bass), but outside Japan this is purely aesthetic as they do not contain their respected Navis. The Battle Chip Gate and Advanced PET II were not released outside Japan.

Trivia

 * It is possible to mod the toy Battle Chips as seen here.
 * On page 172 of the Mega Man Battle Network Official Complete Works, Yuuji Ishihara reveals that the Advanced PET was designed by Takara.