This pretty muchSasuke let him go on purpose. I'm betting that Sasuke is able to track him.
Sasuke is more than capable of subduing this fodder without killing him. Also rinnegan is always active.When was rinnegan active? And who unleashes godly powers against insignificant folders? Also don't forget his journey of redemption; killing people probably isn't so cool with him now.
How did he escape? Did he just run?Sasuke is more than capable of subduing this fodder without killing him. Also rinnegan is always active.