head to head
Neither is harder. They score identically on all four axes, so the difference between them is in kind, not degree.

Optimization · Pure Optimization
A Viking survival game where preparing properly trivialises each biome boss.

Optimization · Pure Optimization
An open-world mech JRPG whose combat rewards deep system and build optimization.
Valheim leans Optimization (Pure Optimization); Xenoblade Chronicles X leans Optimization (Pure Optimization).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Valheim
Block-and-parry timing matters in boss fights.
Xenoblade Chronicles X
positioning and arts timing in combat
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Valheim
Enemies follow scripted AI; no adaptation.
Xenoblade Chronicles X
solo JRPG, no adapting opponent
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Valheim
World seed and biome layout introduce mild randomness.
Xenoblade Chronicles X
drop rates and crit rolls
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Valheim
Gear progression and base infrastructure define progress.
Xenoblade Chronicles X
deep build/skill/gear system to optimize
A matching score does not mean a matching test. Two games can both sit at 10 on execution and demand completely different things of you - which is why the reasoning above matters more than the number beside it.