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.

Variance · Systems & Chaos
Managing dice-roll risk across randomly generated maps with careful party planning.

Variance · Systems & Chaos
Tests probability management as dice rolls repeatedly threaten a doomed Mars mission.
For the King leans Variance (Systems & Chaos); Tharsis leans Variance (Systems & Chaos).
For the King leans a little harder on execution, though the gap is small.
For the King
Turn-based slot rolls need no dexterity
Tharsis
Assigning dice needs no dexterity
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
For the King
Enemies follow simple deterministic combat AI
Tharsis
Disasters are random events, not an adapting mind
Tharsis leans a little harder on variance, though the gap is small.
For the King
Dice-roll combat and random maps dominate single runs
Tharsis
Dice rolls and event draws brutally dominate each turn
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
For the King
Focus economy, routing and loadout play beat the odds
Tharsis
Crew allocation and risk math are the counterplay
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.