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.

Optimization · Pure Optimization
Grand strategy wargame mixing turn-based empire play with real-time battles.

Optimization · Pure Optimization
Engineer a pandemic; evolution order is the puzzle.
Medieval II: Total War leans Optimization (Pure Optimization); Plague Inc: Evolved leans Optimization (Pure Optimization).
Medieval II: Total War leans a little harder on execution, though the gap is small.
Medieval II: Total War
real-time battle micro is modest
Plague Inc: Evolved
no reflex
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Medieval II: Total War
campaign AI is exploitable and mappable
Plague Inc: Evolved
world response scripted
Plague Inc: Evolved leans a little harder on variance, though the gap is small.
Medieval II: Total War
fog of war and event triggers hide some state
Plague Inc: Evolved
country event timing
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Medieval II: Total War
economy, unit counters, and campaign map strategy dominate
Plague Inc: Evolved
evolution order heavily solved
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.