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

Optimization · Pure Optimization
The genre-defining metroidvania with deep RPG systems.

Optimization · Practiced Mastery
Time-manipulation puzzles meet the series' signature weapon-upgrade gunplay.
Castlevania: Symphony of the Night leans Optimization (Pure Optimization); Ratchet & Clank: A Crack in Time leans Optimization (Practiced Mastery).
Ratchet & Clank: A Crack in Time leans a little harder on execution, though the gap is small.
Castlevania: Symphony of the Night
Forgiving action combat
Ratchet & Clank: A Crack in Time
Hoverboot movement, aiming, and time-puzzle dexterity.
Castlevania: Symphony of the Night leans a little harder on reads, though the gap is small.
Castlevania: Symphony of the Night
Scripted bosses
Ratchet & Clank: A Crack in Time
Entirely scripted single-player content.
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Castlevania: Symphony of the Night
Item drops and rare gear
Ratchet & Clank: A Crack in Time
First-pass unknowns in puzzles and arenas.
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Castlevania: Symphony of the Night
Build crafting and sequence breaks
Ratchet & Clank: A Crack in Time
Clank's time puzzles and weapon economy are solvable systems.
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.