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
Space 4X where out-planning the galaxy's economy wins wars before they start.

Optimization · Pure Optimization
An auto-attacker where picking the right weapon evolutions wins by itself.
Galactic Civilizations II: Dread Lords leans Optimization (Pure Optimization); Vampire Survivors leans Optimization (Pure Optimization).
Vampire Survivors leans a little harder on execution, though the gap is small.
Galactic Civilizations II: Dread Lords
Turn-based; zero dexterity
Vampire Survivors
Movement is trivial; no aim or precision required.
Galactic Civilizations II: Dread Lords leans a little harder on reads, though the gap is small.
Galactic Civilizations II: Dread Lords
Acclaimed AI still follows mappable doctrines
Vampire Survivors
Enemies follow fixed spawn scripts; no adaptive opponent.
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Galactic Civilizations II: Dread Lords
Galaxy generation and unexplored starts
Vampire Survivors
Level-up offerings and pickup drops are randomized.
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Galactic Civilizations II: Dread Lords
Economy sliders, ship design, and expansion math dominate
Vampire Survivors
Evolution paths and weapon combinations fully solve the run.
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.