head to head
Song of the Deep asks more than Grand Theft Auto V, and the gap is optimization.

Execution · Practiced Mastery
Sandbox crime playground spanning shooting, driving, and a persistent online economy.

Optimization · Practiced Mastery
A storybook underwater metroidvania about a girl piloting a homemade submarine to find her father.
Grand Theft Auto V leans Execution (Practiced Mastery); Song of the Deep leans Optimization (Practiced Mastery).
Grand Theft Auto V leans a little harder on execution, though the gap is small.
Grand Theft Auto V
Driving and shooting demand decent inputs.
Song of the Deep
Gentle submarine handling and claw manipulation
Grand Theft Auto V leans a little harder on reads, though the gap is small.
Grand Theft Auto V
Online PvP exists but mostly gear/positioning, not modeling.
Song of the Deep
Scripted sea creatures
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Grand Theft Auto V
Some mission and lobby randomness.
Song of the Deep
Unknown undersea map first dive
Song of the Deep leans clearly harder on optimization.
Grand Theft Auto V
Heists, money loops, builds learnable.
Song of the Deep
Environmental puzzles and upgrade routing carry the game
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.