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

Optimization · Practiced Mastery
Co-op first-person zombie RPG about improvised weapons on a resort island.

Optimization · Practiced Mastery
Open-world action game where procedurally generated orc captains remember your encounters.
Dead Island leans Optimization (Practiced Mastery); Middle-earth: Shadow of Mordor leans Optimization (Practiced Mastery).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Dead Island
first-person melee timing and stamina
Middle-earth: Shadow of Mordor
Counter-timing combat and stealth execution
Middle-earth: Shadow of Mordor leans a little harder on reads, though the gap is small.
Dead Island
zombies are scripted swarms
Middle-earth: Shadow of Mordor
Nemesis orcs remember you but remain mappable scripts
Middle-earth: Shadow of Mordor leans a little harder on variance, though the gap is small.
Dead Island
weapon drops and spawns add noise
Middle-earth: Shadow of Mordor
Procedural captains with hidden strengths and weaknesses
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Dead Island
weapon mods and skill builds carry late game
Middle-earth: Shadow of Mordor
Intel gathering and exploiting known weaknesses solves fights
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.