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

Execution · Practiced Mastery
A danmaku arcade shmup where surviving cascading bullet curtains and optimising hyper-cancel chaining pushes execution to its ceiling.

Execution · Pure Mechanics
Arcade run-and-gun whose one-credit clears demand total spawn memorization and twitch.
DoDonPachi DaiFukkatsu leans Execution (Practiced Mastery); Metal Slug 3 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.
DoDonPachi DaiFukkatsu
Surviving dense bullet curtains at high speed demands peak precision
Metal Slug 3
one-hit deaths demand frame-level dodging and aim
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
DoDonPachi DaiFukkatsu
Scripted enemy patterns only - no adaptive opponent
Metal Slug 3
every enemy wave is scripted
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
DoDonPachi DaiFukkatsu
Rank system and some random bullet timings add pressure
Metal Slug 3
branching paths vary runs slightly
DoDonPachi DaiFukkatsu leans a little harder on optimization, though the gap is small.
DoDonPachi DaiFukkatsu
Hyper cancels, chaining, and routing for maximum score are fully solvable
Metal Slug 3
memorizing spawns is the path to a one-credit clear
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.