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

Optimization · Pure Optimization
A perfect-information tactics puzzle solved one turn at a time.

Optimization · Pure Optimization
Grim space colony sim about keeping a generation-ship station from collapsing.
Into the Breach leans Optimization (Pure Optimization); IXION 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.
Into the Breach
No mechanical inputs
IXION
Pause-friendly station management
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Into the Breach
Enemy moves telegraphed fully each turn
IXION
Events follow story scripts
IXION leans a little harder on variance, though the gap is small.
Into the Breach
Light spawn and squad randomness
IXION
System events and exploration outcomes vary
Into the Breach leans a little harder on optimization, though the gap is small.
Into the Breach
Pure puzzle - perfect-information chess each turn
IXION
Hull sectors, power, and population logistics dominate
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.