head to head
Neither is simply harder - they are hard in different places. Muv-Luv Alternative demands more variance; Portal demands more execution.

Optimization · Pure Optimization
A harrowing mecha military story that pays off all investment from the prior two entries.

Optimization · Pure Optimization
The portal-gun puzzle game whose solutions are everything.
Muv-Luv Alternative leans Optimization (Pure Optimization); Portal leans Optimization (Pure Optimization).
Portal leans clearly harder on execution.
Muv-Luv Alternative
No physical demands; pure narrative experience
Portal
Portal placement timing modest.
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Muv-Luv Alternative
BETA enemies are scripted threats, not adaptive opponents
Portal
No adversary modeling player.
Muv-Luv Alternative leans clearly harder on variance.
Muv-Luv Alternative
Hidden timeline information and outcome uncertainty drive tension
Portal
Deterministic chambers; no randomness.
Portal leans clearly harder on optimization.
Muv-Luv Alternative
Following the correct route flags through a linear but choice-gated story
Portal
Pure puzzle-solving optimization.
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.