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
A vault management sim about optimising dwellers, rooms, and resource loops.

Optimization · Pure Optimization
An idle dungeon crawler where you hire bar patrons and script teams to grind dungeons automatically.
Fallout Shelter leans Optimization (Pure Optimization); Soda Dungeon leans Optimization (Pure Optimization).
Soda Dungeon leans a little harder on execution, though the gap is small.
Fallout Shelter
Tapping menus only
Soda Dungeon
Auto-combat does the fighting for you.
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Fallout Shelter
No opponent
Soda Dungeon
Dungeon monsters follow fixed behavior tables.
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Fallout Shelter
Incident spawns and lunchbox loot rolls
Soda Dungeon
Loot rolls and dungeon events add meaningful luck.
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Fallout Shelter
Dweller stats and room layout are fully solvable
Soda Dungeon
Team scripts and gear economy decide run depth.
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.