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

Execution · Pure Mechanics
A top-down war shooter testing dodging and aim through scripted enemy waves.

Execution · Pure Mechanics
An arcade test of jump timing and enemy-flipping precision on a single screen.
Iron Tank: The Invasion of Normandy leans Execution (Pure Mechanics); 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.
Iron Tank: The Invasion of Normandy
Dodging fire and aiming under the scrolling assault is constant
Mario Bros.
Precise jumps and bump timing under crowding enemies decide survival
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Iron Tank: The Invasion of Normandy
Enemies spawn on fixed scripts, no adaptation
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.
Iron Tank: The Invasion of Normandy
Some enemy placement surprises but levels are fixed
Mario Bros.
Enemy spawns vary slightly but patterns are quickly learned
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Iron Tank: The Invasion of Normandy
Weapon powerup management and routing help survival
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.