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
The first fully 3D mainline Pokemon adventure, introducing Mega Evolution and the Fairy type in Kalos.
Clash of Clans leans Optimization (Pure Optimization); Pokemon X leans Optimization (Pure Optimization).
Clash of Clans leans a little harder on execution, though the gap is small.
Clash of Clans
Troop drop placement is forgiving
Pokemon X
Menu-driven combat throughout
Clash of Clans leans a little harder on reads, though the gap is small.
Clash of Clans
Base layouts anticipate human attackers' habits
Pokemon X
Scripted opponents; online battling optional
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
Pokemon X
Wild encounter and catch randomness
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Clash of Clans
Army comps, upgrade paths, and attack routing
Pokemon X
Mega Evolution timing and team planning dominate
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.