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
Optimizing custom race design and tech priorities across a randomly generated galaxy.

Optimization · Pure Optimization
Deep empire optimisation over a hidden map against mappable AI.
Master of Orion (2016) leans Optimization (Pure Optimization); Sid Meier's Civilization IV leans Optimization (Pure Optimization).
Master of Orion (2016) leans a little harder on execution, though the gap is small.
Master of Orion (2016)
Turn-based menus; no physical demands at all
Sid Meier's Civilization IV
Turn-based clicks have no physical ceiling
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Master of Orion (2016)
AI races follow defined personalities without adapting to your play
Sid Meier's Civilization IV
Human multiplayer adds diplomacy reads; AI is mappable
Master of Orion (2016) leans a little harder on variance, though the gap is small.
Master of Orion (2016)
Random galaxy generation and diplomatic outcomes add hidden elements
Sid Meier's Civilization IV
Map generation and unrevealed terrain drive early decisions
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Master of Orion (2016)
Race design, tech priorities, and fleet composition are the solvable core
Sid Meier's Civilization IV
Tech paths, tile yields and expansion math dominate outcomes
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.