Ruminas Valentine (Light Novel) vs Kamen Rider X: who would win?

Ruminas Valentine (Light Novel) favored — Favored (~65%)

Ruminas Valentine (Light Novel) · Tensei Shitara Slime Datta Ken · With Ultimate Skill

Tier

1-C

Attack Potency

Complex Multiverse Level

Speed

Relativistic+, up to Speed Of Light

Durability

Low Complex Multiverse Level

Kamen Rider X · Kamen Rider · Skyrider, Super-1 & ZX

Tier

1-C

Attack Potency

Complex Multiverse Level

Speed

High Hypersonic, up to Ftl+

Durability

Multi-City Block Level, up to Complex Multiverse Level

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