head to head
Zombie Army 4: Dead War asks more than Red Dead Redemption 2, and the gap is execution.

Execution · Practiced Mastery
A cinematic open-world western leaning on shooting feel and atmosphere.

Execution · Practiced Mastery
A co-op horde shooter about sniping waves of occult Nazi undead.
Red Dead Redemption 2 leans Execution (Practiced Mastery); Zombie Army 4: Dead War leans Execution (Practiced Mastery).
Zombie Army 4: Dead War leans clearly harder on execution.
Red Dead Redemption 2
Gunplay and Dead Eye reward aim and timing.
Zombie Army 4: Dead War
Long-range headshots and horde crowd control
Red Dead Redemption 2 leans a little harder on reads, though the gap is small.
Red Dead Redemption 2
Enemies use scripted AI patterns, not adaptation.
Zombie Army 4: Dead War
Undead waves never adapt
Zombie Army 4: Dead War leans a little harder on variance, though the gap is small.
Red Dead Redemption 2
Some hunting and weather randomness, lightly hidden.
Zombie Army 4: Dead War
Spawn variation and elite placement shuffle runs
Zombie Army 4: Dead War leans a little harder on optimization, though the gap is small.
Red Dead Redemption 2
Loadouts and routes solvable but loose.
Zombie Army 4: Dead War
Loadout perks, trap placement, score-chain knowledge
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.