User blog comment:Joji200/Feitan vs Hisoka/@comment-14902757-20150826061514/@comment-14902757-20150826161349

The use of kanmuru in fighting is different from how it's used when Killua is just running. When running, killua's aura does not have an aura to react to. That's why it's leagues slower compared to when fighting. His reflexes become lightning fast when used in fighting while obviously his speed when running does not even come close.. But I agree with you that an enemy can prepare for it if he/she is aware of Killua's ability. If an enemy has more aura, shrouding one's self with it is enough to fend off Killua's attack. If one is unaware and Killua is on assassin mode from the get go, then it's over in a flash for anybody.