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 city placement, social policies, and victory routing under randomized map unknowns.

Optimization · Pure Optimization
Story-heavy deckbuilder of clashing dice and floor-by-floor library combat.
Civilization V leans Optimization (Pure Optimization); Library of Ruina leans Optimization (Pure Optimization).
Civilization V leans a little harder on execution, though the gap is small.
Civilization V
UI actions need no precision; speed is not a factor
Library of Ruina
Turn-based card combat, no input precision.
Civilization V leans a little harder on reads, though the gap is small.
Civilization V
AI follows scripted personalities, not genuine player modelling
Library of Ruina
Scripted enemy decks, no adaptive opponent.
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Civilization V
Random starts, barbarian spawns, and goody huts create hidden unknowns
Library of Ruina
Dice rolls and draws swing fights moderately.
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Civilization V
Hex placement, social policies, and victory routing are fully solvable
Library of Ruina
Deck construction and clash math is deeply 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.