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

Execution · Grand Arena
A combo system built on constant Combo Breaker mind-games that create a unique adaptive read-off at every moment of a combo.

Reads · Grand Arena
A neutral-focused fighter where managing the GRD gauge against an adapting opponent creates a constant strategic tug-of-war.
Killer Instinct (2013) leans Execution (Grand Arena); Under Night In-Birth II Sys:Celes leans Reads (Grand Arena).
Killer Instinct (2013) leans a little harder on execution, though the gap is small.
Killer Instinct (2013)
Shadow counters and Combo Breaker timing demand very precise inputs
Under Night In-Birth II Sys:Celes
GRD-boosted combos and precise Chain Shift timing demand real execution
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Killer Instinct (2013)
Combo Breaker prediction is a pure read-off against an adaptive opponent
Under Night In-Birth II Sys:Celes
GRD tug-of-war with a human opponent is persistently adaptive
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Killer Instinct (2013)
No RNG; all mechanics are fully visible
Under Night In-Birth II Sys:Celes
No RNG; GRD state is visible information
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Killer Instinct (2013)
Instinct activation timing and optimal opener routes are well-studied
Under Night In-Birth II Sys:Celes
GRD management theory and optimal punish routing are well-documented
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.