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
A gravity-based block puzzle testing spatial logic to reach the goal.

Optimization · Pure Optimization
The genre-defining cartoon tower defense with crunchy upgrades and fixed waves begging for perfect solutions.
Crashmo leans Optimization (Pure Optimization); Kingdom Rush 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.
Crashmo
Moving blocks is precise but not twitch-timed
Kingdom Rush
Light micro of hero and rally points
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Crashmo
Solo puzzle with no opponent to predict
Kingdom Rush
Wave compositions are fixed and previewable
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Crashmo
Puzzles are fixed; nothing random to manage
Kingdom Rush
Almost fully deterministic waves
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Crashmo
Solving the gravity-block puzzle is purely a logic solve
Kingdom Rush
Tower placement and upgrade routes 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.