head to head
Neither is meaningfully harder - they pose close to the same test. The widest gap is execution, and it is a single point.

Execution · Practiced Mastery
A cinematic open-world western leaning on shooting feel and atmosphere.

Execution · Practiced Mastery
A top-down shooter about mowing through zombie hordes with upgradable weapons.
Red Dead Redemption 2 leans Execution (Practiced Mastery); Zombie Shooter 2 leans Execution (Practiced Mastery).
Zombie Shooter 2 leans a little harder on execution, though the gap is small.
Red Dead Redemption 2
Gunplay and Dead Eye reward aim and timing.
Zombie Shooter 2
twin-stick aim against zombie hordes
Red Dead Redemption 2 leans a little harder on reads, though the gap is small.
Red Dead Redemption 2
Enemies use scripted AI patterns, not adaptation.
Zombie Shooter 2
scripted zombie waves, no adaptation
Zombie Shooter 2 leans a little harder on variance, though the gap is small.
Red Dead Redemption 2
Some hunting and weather randomness, lightly hidden.
Zombie Shooter 2
loot drops and spawn randomness
Zombie Shooter 2 leans a little harder on optimization, though the gap is small.
Red Dead Redemption 2
Loadouts and routes solvable but loose.
Zombie Shooter 2
weapon upgrade and build optimization
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.