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
The deepest optimization puzzle in the Infinity Engine lineage, rewarding encyclopedic knowledge of 2nd Edition AD&D systems.

Optimization · Pure Optimization
Engineering precise gas, liquid, and power circuits to keep a subterranean colony alive indefinitely.
Baldur's Gate II: Shadows of Amn leans Optimization (Pure Optimization); Oxygen Not Included leans Optimization (Pure Optimization).
Baldur's Gate II: Shadows of Amn leans a little harder on execution, though the gap is small.
Baldur's Gate II: Shadows of Amn
Pause-and-plan removes twitch entirely; micro-placement has marginal value
Oxygen Not Included
All inputs are build-order clicks; no twitch required
Baldur's Gate II: Shadows of Amn leans a little harder on reads, though the gap is small.
Baldur's Gate II: Shadows of Amn
Enemies run scripted behaviour patterns, never modelling your tactics
Oxygen Not Included
No adversary of any kind exists in the colony
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Baldur's Gate II: Shadows of Amn
Loot randomization and enemy ability use create hidden-information layers
Oxygen Not Included
Asteroid seed and geyser placement carry meaningful but bounded randomness
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Baldur's Gate II: Shadows of Amn
Mage spell sequences, dual-class builds and Spellhold routing define mastery
Oxygen Not Included
Gas, liquid, and power engineering are essentially a solvable engineering puzzle
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.