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
A disaster-survival strategy game managing global catastrophes.

Optimization · Pure Optimization
A tactical squad shooter where positioning and probability management outweigh raw aim.
Geostorm leans Optimization (Pure Optimization); The Bureau: XCOM Declassified leans Optimization (Pure Optimization).
The Bureau: XCOM Declassified leans a little harder on execution, though the gap is small.
Geostorm
minor reaction to disaster events
The Bureau: XCOM Declassified
cover shooting timing is moderate
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Geostorm
no adaptive opponent present
The Bureau: XCOM Declassified
alien AI is scripted, no adaptation
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Geostorm
randomized disaster events and outcomes
The Bureau: XCOM Declassified
cover-based hit chances are randomized
The Bureau: XCOM Declassified leans a little harder on optimization, though the gap is small.
Geostorm
resource and defense system management
The Bureau: XCOM Declassified
squad tactics and builds are 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.