head to head
Neither is simply harder - they are hard in different places. Fallout: New Vegas demands more execution; Morphblade demands more variance.

Optimization · Pure Optimization
A faction-driven RPG-shooter where build and route planning shape every ending.

Optimization · Pure Optimization
A turn-based tactics puzzle about chaining weapon transforms against bug waves.
Fallout: New Vegas leans Optimization (Pure Optimization); Morphblade leans Optimization (Pure Optimization).
Fallout: New Vegas leans clearly harder on execution.
Fallout: New Vegas
Shooter inputs with VATS assist
Morphblade
Turn-based movement removes any twitch demand
Fallout: New Vegas leans a little harder on reads, though the gap is small.
Fallout: New Vegas
Scripted factions and enemies
Morphblade
Bugs follow scripted behaviour, not modelling you
Morphblade leans clearly harder on variance.
Fallout: New Vegas
Some loot and crit RNG
Morphblade
Enemy spawn waves have randomised composition
Morphblade leans a little harder on optimization, though the gap is small.
Fallout: New Vegas
Faction routing, perks, builds heavily rewarded
Morphblade
Planning movement to chain weapon transforms optimally is the puzzle
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.