head to head
Neither is simply harder - they are hard in different places. The Witcher 3: Wild Hunt demands more optimization; Warhammer 40,000: Space Marine demands more execution.

Optimization · Practiced Mastery
A narrative action RPG where build planning matters more than reflex execution.

Execution · Practiced Mastery
Third-person action where Captain Titus chainswords through ork hordes without a cover system.
The Witcher 3: Wild Hunt leans Optimization (Practiced Mastery); Warhammer 40,000: Space Marine leans Execution (Practiced Mastery).
Warhammer 40,000: Space Marine leans clearly harder on execution.
The Witcher 3: Wild Hunt
Combat timing matters but generous dodges forgive sloppy play.
Warhammer 40,000: Space Marine
Melee-shooting flow and execution timing carry combat
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
The Witcher 3: Wild Hunt
Enemies use fixed AI behaviours; no adaptation.
Warhammer 40,000: Space Marine
Ork hordes follow scripted aggression
The Witcher 3: Wild Hunt leans a little harder on variance, though the gap is small.
The Witcher 3: Wild Hunt
Loot rolls and minor combat variance only.
Warhammer 40,000: Space Marine
Encounters are fixed and predictable
The Witcher 3: Wild Hunt leans clearly harder on optimization.
The Witcher 3: Wild Hunt
Builds, alchemy, and quest routing reward planning.
Warhammer 40,000: Space Marine
Weapon choice and fury management are simple to learn
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.