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.

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

Execution · Pure Mechanics
An arcade test of jump timing and enemy-flipping precision on a single screen.
12 is Better Than 6 leans Execution (Practiced Mastery); Mario Bros. leans Execution (Pure Mechanics).
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
Mario Bros.
Precise jumps and bump timing under crowding enemies decide survival
Mario Bros. leans a little harder on reads, though the gap is small.
12 is Better Than 6
Enemies are placed and scripted
Mario Bros.
Versus mode adds light human interference, enemies are scripted
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
12 is Better Than 6
Unknown enemy placements on first attempts only
Mario Bros.
Enemy spawns vary slightly but patterns are quickly learned
12 is Better Than 6 leans a little harder on optimization, though the gap is small.
12 is Better Than 6
Each room becomes a learnable clear order
Mario Bros.
POW block usage and enemy routing have known best lines
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.