Haruyama Koichi vs Dr. Robotnik (OVA): who would win?

Haruyama Koichi favored — Slight edge (~55%)

Haruyama Koichi · Crows x Worst · Base

Tier

9-C, up to 9-B

Attack Potency

Street Level, up to Wall Level

Speed

Subsonic

Durability

Street Level, up to Wall Level

Dr. Robotnik (OVA) · Sonic · Base

Tier

9-C, up to LOW 7-B

Attack Potency

Street Level, up to Small City Level

Speed

Average Human, up to Massively Hypersonic

Durability

Street Level, up to Small City Level

A heuristic estimate from normalized VS Battles Wiki stats: tier, attack potency, speed and durability.