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.

Optimization · Pure Optimization
Base-building strategy game about optimizing upgrade economy and raid compositions.

Optimization · Pure Optimization
A voice-controlled tactics game testing command planning and unit positioning.
Clash of Clans leans Optimization (Pure Optimization); There Came an Echo leans Optimization (Pure Optimization).
There Came an Echo leans a little harder on execution, though the gap is small.
Clash of Clans
Troop drop placement is forgiving
There Came an Echo
Voice commands need no physical dexterity
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Clash of Clans
Base layouts anticipate human attackers' habits
There Came an Echo
Enemy AI scripted, allows limited prediction only
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Clash of Clans
Matchmaking and unseen traps add uncertainty
There Came an Echo
Voice recognition and combat add some unpredictability
Clash of Clans leans a little harder on optimization, though the gap is small.
Clash of Clans
Army comps, upgrade paths, and attack routing
There Came an Echo
Issuing positioning and timing commands wins encounters
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.