Firestorm (Pre-Crisis) vs Mina Ashiro: who would win?

Mina Ashiro favored — Slight edge (~55%)

Firestorm (Pre-Crisis) · DC · Base

Tier

HIGH 6-B

Attack Potency

Large Country Level

Speed

Supersonic, up to Massively Ftl+

Durability

City Level

Mina Ashiro · Kaiju No. 8 · Base

Tier

HIGH 6-B, up to HIGH 6-A

Attack Potency

Large Country Level, up to Multi-Continent Level

Speed

High Hypersonic, up to Ftl

Durability

Mountain Level+, up to Large Country Level

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