Grunbeld vs Ittan: who would win?

Grunbeld favored — Slight edge (~55%)

Grunbeld · Berserk · Base

Tier

8-A

Attack Potency

Multi-City Block Level

Speed

Massively Hypersonic

Durability

Multi-City Block Level

Ittan · Naruto · Base

Tier

8-A

Attack Potency

Multi-City Block Level

Speed

Hypersonic, up to Massively Hypersonic+

Durability

Multi-City Block Level

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