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.

Variance · Pure Chaos
Tests nothing but luck - a spectator marble race decided entirely by physics RNG.

Variance · Pure Chaos
A family board game where the spinner, not skill, decides who retires richest.
Marbles on Stream leans Variance (Pure Chaos); The Game of Life 2 leans Variance (Pure Chaos).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Marbles on Stream
You watch a marble roll; no inputs matter
The Game of Life 2
Spinning a virtual wheel takes nothing
The Game of Life 2 leans a little harder on reads, though the gap is small.
Marbles on Stream
No opponent decisions exist to predict
The Game of Life 2
Opponents' choices barely interact with yours
The Game of Life 2 leans a little harder on variance, though the gap is small.
Marbles on Stream
Physics RNG decides the entire race outcome
The Game of Life 2
The spinner and card draws decide nearly everything
The Game of Life 2 leans a little harder on optimization, though the gap is small.
Marbles on Stream
Nothing to solve beyond picking a marble skin
The Game of Life 2
A few path choices nudge expected value slightly
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.