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
Moody Halo side story about ordinary troopers piecing together a night in New Mombasa.

Execution · Practiced Mastery
Robot-dinosaur hunting that rewards weak-point study and ranged precision.
Halo 3: ODST leans Execution (Practiced Mastery); Horizon Zero Dawn leans Execution (Practiced Mastery).
Halo 3: ODST leans a little harder on execution, though the gap is small.
Halo 3: ODST
Squishier soldier demands careful aim and positioning
Horizon Zero Dawn
Bow aiming and dodge timing matter.
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Halo 3: ODST
Covenant patrols are scripted, not adaptive
Horizon Zero Dawn
Machines follow fixed patterns, not adapting.
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Halo 3: ODST
Open Mombasa hides clues until found
Horizon Zero Dawn
Some loot and patrol randomness.
Halo 3: ODST leans a little harder on optimization, though the gap is small.
Halo 3: ODST
Firefight wave knowledge and route planning
Horizon Zero Dawn
Weak points, traps, builds fully solvable.
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.