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

Execution · Practiced Mastery
Toy-car arcade racer about drift-charging boost on loop-the-loop tracks.

Execution · Practiced Mastery
A classic arcade brawler sending the turtles through time to pummel Foot Clan waves.
Hot Wheels Unleashed leans Execution (Practiced Mastery); Teenage Mutant Ninja Turtles IV: Turtles in Time leans Execution (Practiced Mastery).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Hot Wheels Unleashed
Drift-boost management on twisting plastic tracks
Teenage Mutant Ninja Turtles IV: Turtles in Time
Throw timing, positioning, and boss dodges are the whole test.
Hot Wheels Unleashed leans a little harder on reads, though the gap is small.
Hot Wheels Unleashed
Online races add light human jockeying
Teenage Mutant Ninja Turtles IV: Turtles in Time
Foot Soldiers run fixed scripts.
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Hot Wheels Unleashed
Car unboxing randomness outside races
Teenage Mutant Ninja Turtles IV: Turtles in Time
Stages and waves are essentially fixed.
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Hot Wheels Unleashed
Car tiers, upgrades, and racing lines
Teenage Mutant Ninja Turtles IV: Turtles in Time
Wave layouts and boss patterns are fully memorisable.
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.
full breakdown
Hot Wheels Unleashed →
full breakdown
Teenage Mutant Ninja Turtles IV: Turtles in Time →