head to head
Neither is meaningfully harder - they pose close to the same test. The widest gap is reads, and it is a single point.

Optimization · Pure Optimization
A wave-defense RTS testing economic and defensive optimization against scripted hordes.

Optimization · Pure Optimization
Designing animal habitats that satisfy complex welfare systems while maintaining zoo profitability.
Diplomacy is Not an Option leans Optimization (Pure Optimization); Planet Zoo leans Optimization (Pure Optimization).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Diplomacy is Not an Option
Fast unit micro helps but isn't the ceiling
Planet Zoo
Animal habitat and path construction demands deliberate precision
Diplomacy is Not an Option leans a little harder on reads, though the gap is small.
Diplomacy is Not an Option
Enemy hordes follow scripted waves, not adapting
Planet Zoo
Animals and guests follow scripted need systems
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Diplomacy is Not an Option
Some map and event variation, mostly fixed
Planet Zoo
Animal welfare stats have minor stochastic variation
Diplomacy is Not an Option leans a little harder on optimization, though the gap is small.
Diplomacy is Not an Option
Economy, defenses and army composition against scaling waves
Planet Zoo
Species welfare requirements and financial management are fully 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.