head to head
Neither is harder. They score identically on all four axes, so the difference between them is in kind, not degree.

Optimization · Pure Optimization
Physics sandbox about engineering medieval siege machines that usually explode beautifully.

Optimization · Pure Optimization
A physics sandbox testing track design to guide a sledder along drawn lines.
Besiege leans Optimization (Pure Optimization); Line Rider 2: Unbound 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.
Besiege
Piloting wobbly contraptions takes some hand skill
Line Rider 2: Unbound
Drawing tracks has no twitch dimension
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Besiege
Static castles and scripted defenders
Line Rider 2: Unbound
Solo physics sandbox with no opponent
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Besiege
Deterministic physics and fixed objectives
Line Rider 2: Unbound
Deterministic physics, nothing random
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Besiege
Machine engineering is the whole game
Line Rider 2: Unbound
Designing tracks that produce desired sled physics is the puzzle
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.