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
An open-world RPG mostly about discovering and stacking exploitable progression systems.

Optimization · Pure Optimization
CD Projekt's first RPG, a dark fantasy of monster contracts and morally gray choices.
The Elder Scrolls V: Skyrim leans Optimization (Pure Optimization); The Witcher 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.
The Elder Scrolls V: Skyrim
Combat is forgiving; aim and timing rarely punish you.
The Witcher
Rhythm-click combat needs only loose timing
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
The Elder Scrolls V: Skyrim
Enemy AI is scripted and exploitable; not adaptive.
The Witcher
Enemies follow fixed styles and weaknesses
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
The Elder Scrolls V: Skyrim
Loot tables and leveled lists inject mild randomness.
The Witcher
Some unknown quest outcomes on first play
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
The Elder Scrolls V: Skyrim
Skill stacking, enchant loops, and exploits are deeply solvable.
The Witcher
Signs, potions, and style matchups form the real game
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.