head to head
Fallout: New Vegas asks more than Lost Grimoires 2: Shard of Mystery, and the gap is execution.

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

Optimization · Pure Optimization
A puzzle adventure built on solving fixed alchemy and logic challenges.
Fallout: New Vegas leans Optimization (Pure Optimization); Lost Grimoires 2: Shard of Mystery leans Optimization (Pure Optimization).
Fallout: New Vegas leans clearly harder on execution.
Fallout: New Vegas
Shooter inputs with VATS assist
Lost Grimoires 2: Shard of Mystery
Click-driven with no twitch demands
Fallout: New Vegas leans a little harder on reads, though the gap is small.
Fallout: New Vegas
Scripted factions and enemies
Lost Grimoires 2: Shard of Mystery
No adaptive opponent in this solo story
Fallout: New Vegas leans a little harder on variance, though the gap is small.
Fallout: New Vegas
Some loot and crit RNG
Lost Grimoires 2: Shard of Mystery
Puzzles are fixed once examined, not random
Fallout: New Vegas leans clearly harder on optimization.
Fallout: New Vegas
Faction routing, perks, builds heavily rewarded
Lost Grimoires 2: Shard of Mystery
Alchemy crafting and puzzle logic are the solvable core
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.