In Mega Man Battle Network 3, if Lan uses a Navi Customizer program that the current Style did not support and rebooted MegaMan.EXE, he'd get an error, MegaMan would not be able to boot up, unless remedied with an Extra Code. However, in the fourth, fifth, and sixth games, the errors disappeared due to MegaMan overloading to destroy Alpha. In doing so, he nearly killed himself, but when Lan gives Yuichiro Tadashi Hikari's letter, MegaMan is recovered from Alpha's body. However, his letter removed the Style Change. So, Double Soul was made as a suitable replacement.