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

Execution · Pure Mechanics
Classic arena aim married to champion abilities, tested against adaptive human opponents in fast duel maps.

Execution · Pure Mechanics
A fast arena shooter where twitch aim and movement against human opponents is everything.
Quake Champions leans Execution (Pure Mechanics); Unreal Tournament 2003 leans Execution (Pure Mechanics).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Quake Champions
Champion abilities add execution layers on top of classic rail and rocket aim
Unreal Tournament 2003
aim and movement speed decide duels
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Quake Champions
Human duels require reading opponent ability usage and positioning
Unreal Tournament 2003
predicting human opponent positioning
Quake Champions leans a little harder on variance, though the gap is small.
Quake Champions
Ability cooldowns introduce mild timing uncertainty per match
Unreal Tournament 2003
weapon and pickup spawns vary
Quake Champions leans a little harder on optimization, though the gap is small.
Quake Champions
Champion matchup knowledge and item timing are solvable advantages
Unreal Tournament 2003
map control and item timing solvable
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.