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

Optimization · Pure Optimization
A spiritual successor to classic Castlevania metroidvanias.

Optimization · Pure Optimization
The Game Boy expedition that turns Metroid into a methodical extermination checklist deep inside SR388.
Bloodstained: Ritual of the Night leans Optimization (Pure Optimization); Metroid II: Return of Samus 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.
Bloodstained: Ritual of the Night
Action combat with modest demands
Metroid II: Return of Samus
Cramped Game Boy combat against Metroid forms.
Bloodstained: Ritual of the Night leans a little harder on reads, though the gap is small.
Bloodstained: Ritual of the Night
Scripted bosses
Metroid II: Return of Samus
Creatures follow fixed behaviours.
Bloodstained: Ritual of the Night leans a little harder on variance, though the gap is small.
Bloodstained: Ritual of the Night
Shard and crafting drops
Metroid II: Return of Samus
Disorienting unknown caverns until mapped.
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Bloodstained: Ritual of the Night
Shard builds and crafting routes
Metroid II: Return of Samus
Hunting all 39 Metroids is methodical route work.
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.