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
One-hit-death shmup execution through memorised alien-intestine stage patterns.

Execution · Pure Mechanics
Peak 16-bit run-and-gun of set-piece bosses and razor-thin dodges.
Abadox: The Deadly Inner War leans Execution (Pure Mechanics); Contra III: The Alien Wars 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.
Abadox: The Deadly Inner War
One-hit deaths make every dodge a perfect-input demand
Contra III: The Alien Wars
Relentless bosses and bullet dodging
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Abadox: The Deadly Inner War
Enemy waves are fully scripted
Contra III: The Alien Wars
Set-piece bosses are pure scripts
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Abadox: The Deadly Inner War
Stages replay identically once seen
Contra III: The Alien Wars
Everything is fixed and learnable
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Abadox: The Deadly Inner War
Memorising spawns and checkpoint routes is mandatory
Contra III: The Alien Wars
Weapon management and pattern 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.