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
Optimising tower placement, research and economy against scripted alien waves.

Optimization · Pure Optimization
A 2D sandbox where preparation and gear tiering carry boss fights.
Revenge of the Titans leans Optimization (Pure Optimization); Terraria leans Optimization (Pure Optimization).
Terraria leans a little harder on execution, though the gap is small.
Revenge of the Titans
Mid-wave building rewards speed but never twitch-defines outcomes
Terraria
Boss fights require dodging and aim under pressure.
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Revenge of the Titans
Titan waves follow set paths without adapting
Terraria
Bosses use scripted attacks; no adaptation.
Terraria leans a little harder on variance, though the gap is small.
Revenge of the Titans
Wave compositions are unknown on a first campaign run
Terraria
World seeds and loot drops randomized.
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Revenge of the Titans
Tech choices, placement and economy are the whole game
Terraria
Gear progression and arena prep solve every boss.
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.