Bugs:Mega Man Battle Network 4
This page details bugs of Mega Man Battle Network 4.
WoodMan Scenario Bug on Nintendo DS
During WoodMan's scenario in the second tournament, the game might slow down severely when played on an original Nintendo DS if a menu or battle is accessed in Park Area. This occurs on DS' hardware level because the game fails to check the need to reset animation frame reset index when Wood Towers are there, resulting in an attempt to load a non-existent sprite from an invalid memory address. The DS hardware treats this data as a continuous sprite data, resulting in the near-hang slowdown as the game attempts to wrap back to mapped, valid memory.
Nintendo acknowledged this bug on their website, although only Blue Moon is credited; the bug can also occur on Red Sun.
Certain Navi Chips such as GutsMan are programmed incorrectly, causing the game to freeze; like the WoodMan Scenario Bug, this is exclusive to early emulations (such as older versions of Visual Boy Advance). These bugs were also fixed in-software in the Virtual Console release and the Legacy Collection.
BurnerMan Hitbox Bug
Destroying BurnerMan's torches while they are attacking causes the hitbox to remain for a certain time, damaging the player; this bug is also present in 4.5, but is much harder to replicate due to its automated movement.