Dr. Mesfield (メスフィールド Mesufīrudo?) was a Tipharean scientist created by the GENE Project who invented the D-Ripper, which is implanted in Tunpò's body. His brain bio-chip was at some point acquired by Aga Mbadi.
Mesfield's history was not revealed. He would have created the D-Ripper at some point after the Second Zenith of Things Tournament in ES 501, as Tunpò acquired it afterwards. Likely after arriving at Ketheres, Mesfield was captured by Aga Mbadi and had his brain bio-chip extracted and implanted into his own brain.
All of Mbadi's bio-chips were later removed and destroyed by Tunpò in ES 591, finally ending the lives of all three scientists.