head to head
Neither is harder. They score identically on all four axes, so the difference between them is in kind, not degree.

Variance · Systems & Chaos
Listening for randomised audio cues and executing a defensive checking routine.

Variance · Systems & Chaos
A tile-connection puzzle about routing fuses into chain reactions from random pieces.
Five Nights at Freddy's 4 leans Variance (Systems & Chaos); Rocket Mania Deluxe leans Variance (Systems & Chaos).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Five Nights at Freddy's 4
Reacting to breath audio cues within tight windows matters
Rocket Mania Deluxe
Timed mode rewards speed but placement is deliberate
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Five Nights at Freddy's 4
Animatronic movement is RNG, not an adapting mind
Rocket Mania Deluxe
Solo - no opponent to predict
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Five Nights at Freddy's 4
Random animatronic positions stay hidden behind audio cues
Rocket Mania Deluxe
Random fuse pieces drive each board's possibilities
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Five Nights at Freddy's 4
Door-checking routines become a learnable optimal loop
Rocket Mania Deluxe
Planning chain-reaction connections maximizes rocket launches
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.