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
A Revolution-era Paris entry built around dense crowds and open-ended blackbox assassinations.

Optimization · Practiced Mastery
A long Viking RPG carried by exploration and gear progression.
Assassin's Creed Unity leans Optimization (Practiced Mastery); Assassin's Creed Valhalla 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.
Assassin's Creed Unity
Refined parkour, still forgiving combat
Assassin's Creed Valhalla
Combat timing matters but forgiving.
Assassin's Creed Valhalla leans a little harder on reads, though the gap is small.
Assassin's Creed Unity
Co-op partners face scripted guards
Assassin's Creed Valhalla
Enemies scripted and predictable.
Assassin's Creed Valhalla leans a little harder on variance, though the gap is small.
Assassin's Creed Unity
Fixed sandbox assassinations
Assassin's Creed Valhalla
Loot rolls and raid encounters vary mildly.
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Assassin's Creed Unity
Gear builds and blackbox approach planning
Assassin's Creed Valhalla
Skill tree, gear, raid routing 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.