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 fast mech-action game where assembling the right build and piloting it hard both decide bosses.

Optimization · Practiced Mastery
Threading precise inputs through scripted guard gauntlets aboard a controlled and memorisable facility.
Armored Core VI: Fires of Rubicon leans Execution (Practiced Mastery); Metal Gear Solid 2: Sons of Liberty leans Optimization (Practiced Mastery).
Armored Core VI: Fires of Rubicon leans a little harder on execution, though the gap is small.
Armored Core VI: Fires of Rubicon
Boss fights demand sharp dodges and stagger timing
Metal Gear Solid 2: Sons of Liberty
First-person aim and guard reaction windows demand precise input
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Armored Core VI: Fires of Rubicon
Campaign bosses are scripted; PvP is niche
Metal Gear Solid 2: Sons of Liberty
Guards radio for backup on scripted triggers, not adaptive tactics
Metal Gear Solid 2: Sons of Liberty leans a little harder on variance, though the gap is small.
Armored Core VI: Fires of Rubicon
Fixed encounters
Metal Gear Solid 2: Sons of Liberty
Alert timers and item pickups create some hidden-state tension
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Armored Core VI: Fires of Rubicon
Build crafting trivializes many bosses
Metal Gear Solid 2: Sons of Liberty
Chokepoint memorisation and radar manipulation are learnable and repeatable
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.
full breakdown
Armored Core VI: Fires of Rubicon →
full breakdown
Metal Gear Solid 2: Sons of Liberty →