head to head
Neither is harder. They score identically on all four axes, so the difference between them is in kind, not degree.

Optimization · Systems & Chaos
A solo poker roguelike about engineering scoring engines from a randomised shop.

Optimization · Systems & Chaos
An enormous open-world survival roguelike simulating everything from crafting to vehicle building after the apocalypse.
Balatro leans Optimization (Systems & Chaos); Cataclysm: Dark Days Ahead leans Optimization (Systems & Chaos).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Balatro
Drag-and-click cards; no mechanical demand at all.
Cataclysm: Dark Days Ahead
Turn-based; only patience required
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Balatro
No opponent; blinds are fixed scripted targets.
Cataclysm: Dark Days Ahead
Zombies and factions follow mappable behaviour
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Balatro
Shop offers and card draws gate every run.
Cataclysm: Dark Days Ahead
Procedural world and scavenging luck shape early survival
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Balatro
Joker synergies and scoring math are the core puzzle.
Cataclysm: Dark Days Ahead
Crafting, vehicles, and base systems reward near-endless mastery
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.