head to head
Neither is simply harder - they are hard in different places. Portal 2 demands more execution; Skulls of the Shogun demands more reads.

Optimization · Pure Optimization
A first-person puzzle game where seeing the solution is the whole skill.

Optimization · Pure Optimization
Tests turn-based positioning and resource play, sharpened by human opponents online.
Portal 2 leans Optimization (Pure Optimization); Skulls of the Shogun leans Optimization (Pure Optimization).
Portal 2 leans clearly harder on execution.
Portal 2
Portal placement requires some precision but timing is lenient.
Skulls of the Shogun
Turn-based orders need no dexterity
Skulls of the Shogun leans clearly harder on reads.
Portal 2
No opponent; puzzles are static.
Skulls of the Shogun
Human multiplayer rewards anticipating opponent plans
Skulls of the Shogun leans clearly harder on variance.
Portal 2
Puzzles are deterministic with no randomness.
Skulls of the Shogun
Little hidden beyond minor attack variance
Portal 2 leans a little harder on optimization, though the gap is small.
Portal 2
Solving the puzzle's logic IS the entire game.
Skulls of the Shogun
Positioning, skull-eating economy and zone control are 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.