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
Cinematic survival action where scavenged resources and stealth carry you through the apocalypse.
Halo 3: ODST leans Execution (Practiced Mastery); The Last of Us 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
The Last of Us
Aim, stealth timing, and scarce-ammo combat
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
The Last of Us
Enemy AI searches but follows mappable routines
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
The Last of Us
Encounter layouts unknown first time only
Halo 3: ODST leans a little harder on optimization, though the gap is small.
Halo 3: ODST
Firefight wave knowledge and route planning
The Last of Us
Resource crafting and encounter routing
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.