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 · Pure Mechanics
A twin-stick arcade shooter testing aim and web defense reflexes.

Execution · Pure Mechanics
An arcade test of jump timing and enemy-flipping precision on a single screen.
Black Widow leans Execution (Pure Mechanics); Mario Bros. leans Execution (Pure Mechanics).
Black Widow leans a little harder on execution, though the gap is small.
Black Widow
Twin-stick aiming and movement on the web is the core test
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.
Black Widow
Bugs follow scripted spawn patterns, not adapting
Mario Bros.
Versus mode adds light human interference, enemies are scripted
Black Widow leans a little harder on variance, though the gap is small.
Black Widow
Bug entry points add mild unpredictability
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.
Black Widow
Prioritizing targets and bonus timing raises scores
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.