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
An on-rails comedic shooter testing precise aim against scripted waves.

Execution · Pure Mechanics
A classic beat-em-up demanding execution against scripted enemy waves.
Gal*Gun 2 leans Execution (Pure Mechanics); Teenage Mutant Ninja Turtles III: The Manhattan Project leans Execution (Pure Mechanics).
Teenage Mutant Ninja Turtles III: The Manhattan Project leans a little harder on execution, though the gap is small.
Gal*Gun 2
on-rails aiming and timing precision
Teenage Mutant Ninja Turtles III: The Manhattan Project
beat-em-up timing and enemy juggling
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Gal*Gun 2
scripted enemy waves, no adaptation
Teenage Mutant Ninja Turtles III: The Manhattan Project
enemies run simple fixed scripts
Gal*Gun 2 leans a little harder on variance, though the gap is small.
Gal*Gun 2
minor randomness in encounters
Teenage Mutant Ninja Turtles III: The Manhattan Project
minor enemy spawn randomness
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Gal*Gun 2
weapon/route choice
Teenage Mutant Ninja Turtles III: The Manhattan Project
character choice and route memorization
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.