head to head
Neither is simply harder - they are hard in different places. Arena Breakout: Infinite demands more variance; StarCraft II: Wings of Liberty demands more execution.

Execution · Grand Arena
High-stakes extraction raids testing aim, opponent prediction, and loot-economy mastery at once.

Execution · Grand Arena
Real-time strategy where hands, reads, and build optimization all matter at the top.
Arena Breakout: Infinite leans Execution (Grand Arena); StarCraft II: Wings of Liberty leans Execution (Grand Arena).
StarCraft II: Wings of Liberty leans clearly harder on execution.
Arena Breakout: Infinite
Gunfights against humans punish slow aim instantly
StarCraft II: Wings of Liberty
APM, macro, micro-control under pressure
StarCraft II: Wings of Liberty leans clearly harder on reads.
Arena Breakout: Infinite
Predicting other squads' rotations and ambushes is constant
StarCraft II: Wings of Liberty
1v1 ladder vs adaptive humans modeling you
Arena Breakout: Infinite leans clearly harder on variance.
Arena Breakout: Infinite
Loot spawns and unseen player positions dominate raid outcomes
StarCraft II: Wings of Liberty
map spawns minor; mostly known
StarCraft II: Wings of Liberty leans a little harder on optimization, though the gap is small.
Arena Breakout: Infinite
Ammo tiers, insurance economy and map routes reward deep study
StarCraft II: Wings of Liberty
build orders, economy curves heavily solved
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.