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

Execution · Pure Mechanics
A PS4-era Killzone where a Shadow Marshal and his OWL drone fight through a divided Helghast city.

Execution · Pure Mechanics
Console shooter execution across scripted set pieces and once-massive human multiplayer.
Killzone Shadow Fall leans Execution (Pure Mechanics); Resistance 2 leans Execution (Pure Mechanics).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Killzone Shadow Fall
Standard FPS aim and movement ceiling
Resistance 2
Weapon handling and boss dodging demand console-shooter precision
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Killzone Shadow Fall
PvP modes reward predicting human players
Resistance 2
60-player multiplayer rewarded reading humans; campaign Chimera don't adapt
Killzone Shadow Fall leans a little harder on variance, though the gap is small.
Killzone Shadow Fall
Some open level routes and spawn noise
Resistance 2
Campaign encounters are set pieces
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Killzone Shadow Fall
OWL drone usage and loadouts optimize cleanly
Resistance 2
Exotic weapon choice and class co-op roles add planning
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.