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 · Pure Mechanics
A relentless wave-clearing shooter that tests sustained aim and movement against massive scripted enemy crowds.

Execution · Pure Mechanics
A bullet-grazing shoot-em-up about leveling by skimming enemy fire as closely as possible.
Painkiller (2004) leans Execution (Pure Mechanics); Psyvariar Delta leans Execution (Pure Mechanics).
Psyvariar Delta leans a little harder on execution, though the gap is small.
Painkiller (2004)
Constant crowd-control movement against overwhelming enemy counts demands fast aim
Psyvariar Delta
Grazing bullets at the edge of death defines mastery
Psyvariar Delta leans a little harder on reads, though the gap is small.
Painkiller (2004)
All enemies are scripted waves with fixed attack patterns
Psyvariar Delta
Enemy fire is scripted, not adaptive
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Painkiller (2004)
Enemy counts and placements are fixed with minimal unknown elements
Psyvariar Delta
Patterns are fixed and memorizable
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Painkiller (2004)
Tarot card selection and level routing provide a thin solvable layer
Psyvariar Delta
Buzz-chaining routes and leveling strategy reward planning
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.