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

Optimization · Practiced Mastery
A dungeon-crawler spin-off testing build management across randomised otherworlds.

Optimization · Practiced Mastery
Routing efficient digs and upgrades through a randomised mine.
Silent Hill: Book of Memories leans Optimization (Practiced Mastery); SteamWorld Dig leans Optimization (Practiced Mastery).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Silent Hill: Book of Memories
Twin-stick melee and dodge timing matter moderately
SteamWorld Dig
Digging and platforming need modest precision
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Silent Hill: Book of Memories
Monsters follow simple scripted aggression
SteamWorld Dig
Enemies follow simple fixed patterns
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Silent Hill: Book of Memories
Procedural dungeon layouts and loot rolls vary each run
SteamWorld Dig
Randomised mine layouts hide ore and hazards each run
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Silent Hill: Book of Memories
Karma builds, weapon upkeep and puzzle rooms reward system mastery
SteamWorld Dig
Upgrade routing and efficient dig paths drive progress
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.