head to head
Neither is simply harder - they are hard in different places. StarCraft demands more execution; Yu-Gi-Oh! Duel Links demands more variance.

Optimization · Grand Arena
A real-time strategy classic where perfected build orders and mechanical speed decide most matches.

Optimization · Grand Arena
A fast-format digital Yu-Gi-Oh! card game built around ranked PvP and meta decks.
StarCraft leans Optimization (Grand Arena); Yu-Gi-Oh! Duel Links leans Optimization (Grand Arena).
StarCraft leans clearly harder on execution.
StarCraft
APM and micro control ceiling is huge
Yu-Gi-Oh! Duel Links
Tapping cards, no dexterity test
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
StarCraft
scouting and predicting human opponent builds
Yu-Gi-Oh! Duel Links
Ranked PvP rewards predicting set cards and bluffs
Yu-Gi-Oh! Duel Links leans clearly harder on variance.
StarCraft
minimal hidden info beyond fog of war
Yu-Gi-Oh! Duel Links
Draws and unknown opponent decks dominate
StarCraft leans a little harder on optimization, though the gap is small.
StarCraft
build orders and economy are near-solvable
Yu-Gi-Oh! Duel Links
Meta deckbuilding and line calculation are the spine
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.