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

Execution · Practiced Mastery
A hand-drawn western take on Hotline Miami where you cock the revolver before every single shot.

Execution · Practiced Mastery
Arcade western shooter narrated as a bounty hunter's tall tale.
12 is Better Than 6 leans Execution (Practiced Mastery); Call of Juarez: Gunslinger leans Execution (Practiced Mastery).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
12 is Better Than 6
One-hit deaths, manual cocking, fast top-down aim
Call of Juarez: Gunslinger
Quick-draw duels and combo shooting demand precision
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
12 is Better Than 6
Enemies are placed and scripted
Call of Juarez: Gunslinger
Enemies are scripted gallery targets
12 is Better Than 6 leans a little harder on variance, though the gap is small.
12 is Better Than 6
Unknown enemy placements on first attempts only
Call of Juarez: Gunslinger
Minor enemy placement surprises first run
Call of Juarez: Gunslinger leans a little harder on optimization, though the gap is small.
12 is Better Than 6
Each room becomes a learnable clear order
Call of Juarez: Gunslinger
Score routes, skill trees, duel timing knowledge
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.