Artemis (Fate) vs Surtr (Fire Emblem): who would win?

Surtr (Fire Emblem) favored — Slight edge (~55%)

Artemis (Fate) · Nasuverse · True Form

Tier

1-C

Attack Potency

Complex Multiverse Level

Speed

Immobile, up to Immeasurable

Durability

Complex Multiverse Level

Surtr (Fire Emblem) · Fire Emblem · Book II

Tier

1-C

Attack Potency

Complex Multiverse Level

Speed

Superhuman, up to Massively Hypersonic+

Durability

Complex Multiverse Level

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