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

Execution · Grand Arena
Open military simulator and PvP sandbox.

Execution · Grand Arena
Hero shooter with team-up ability synergies.
Arma 3 leans Execution (Grand Arena); Marvel Rivals leans Execution (Grand Arena).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Arma 3
Bullet drop, stance, sway, weight all matter
Marvel Rivals
Hero aim and ability timing
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Arma 3
PvP and milsim ops reward prediction
Marvel Rivals
Team-fight cooldown trading is prediction
Arma 3 leans a little harder on variance, though the gap is small.
Arma 3
Mission scripts and AI behavior vary
Marvel Rivals
Map and team comp roll affects
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Arma 3
Loadout planning and tactics solvable
Marvel Rivals
Hero synergies and team-up combos deep
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.