It is the third game in the Mega Man Battle Network series, released in 2002 in Japan and 2003 in North America.

Doctor Wily has reformed the evil organization WWW (World Three) and now seeks to release Alpha, a prototype version of the Internet that went berserk after becoming corrupted by bugs and was locked away before the current Net was set up.

To release it, Wily needs the passwords, referred to in-game as TetraCodes, to the firewalls Alpha is trapped behind, which are hidden in secret locations.

It is later revealed to be part of the plan for Wily to steal the TetraCodes, and the WWW attacks between rounds.

Lan and MegaMan confront Wily immediately after he releases Alpha, and battle Bass.

Later, Lan's father manages to recover MegaMan during a salvage operation of the affected network location, and is able to revive him.

There are certain types of programs (see Navi Customizer) that can boost the Mega and Giga chip limits, though.

When you enter the Multiplayer screen, the player can choose from Netbattling, Trading Chips, and Comparing Libraries.

Practice allows two players to battle with no risk of losing chips, and does not count against your Win/Loss record.

Lightweight allows players to battle on a level field, with no negative panels on either side.

Midweight may give certain obstacles on either player's side of the field, such as Rockcubes and plain Rocks.

From here, the player can buy that Chip from Higsby's shop in ACDC Town after the defeat of Beastman; using the Order System.

[15] The game appeared within the Famitsu top 30 best-sellers list for twelve weeks following its release with 461,426 units sold by March 16, 2003.