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 · Pure Mechanics
Arcade racing with Mario Kart-style power-ups bolted onto licensed cars.

Execution · Twitch Chaos
A scarcity-driven aim test under randomised objectives and spawns.
Blur leans Execution (Pure Mechanics); Contagion leans Execution (Twitch Chaos).
Blur leans a little harder on execution, though the gap is small.
Blur
Racing lines and dodging shots demand car control
Contagion
Deliberate aim with scarce ammo decides zombie encounters
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Blur
Human racers bait and time power-ups against you
Contagion
Hunted mode pits humans against humans; zombies are mindless
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Blur
Power-up pickups and incoming attacks add chaos
Contagion
Randomised objectives, spawns and routes reshape every round
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Blur
Track knowledge and pickup routes are learnable
Contagion
Resource discipline and map knowledge carry survival
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.