E-111 Mu was an E-100 Series robot.
Mu was the twelfth E-Series robot created by Dr. Eggman. At some point it was stationed near Mazuri alongside E-112 Nu. It and its brother ambushed E-102 Gamma, but both were defeated and their Mobini batteries freed. (ASUB)
- Mu was never formally introduced in the comics, but his fate was revealed in the (now defunct) Sonic Universe blogs.