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.

Execution · Practiced Mastery
Anime soulslike pairing pattern-learning boss fights with flexible class builds.

Execution · Practiced Mastery
A lean souls-like carried by hardened-parry timing and shell selection.
Code Vein leans Execution (Practiced Mastery); Mortal Shell leans Execution (Practiced Mastery).
Mortal Shell leans a little harder on execution, though the gap is small.
Code Vein
Dodge timing and stamina management in melee
Mortal Shell
Hardened parry timing demands inputs
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Code Vein
Bosses are scripted patterns, never adaptive
Mortal Shell
Scripted bosses
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Code Vein
Fixed enemy placement; minor drop randomness
Mortal Shell
Minor item randomness
Code Vein leans a little harder on optimization, though the gap is small.
Code Vein
Blood codes and gift builds reward theorycraft
Mortal Shell
Shell choice and upgrade routing matter
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.