head to head
vs
Fire Emblem HeroesvsStygian: Reign of the Old Ones
Fire Emblem Heroes leans Optimization (Systems & Chaos); Stygian: Reign of the Old Ones leans Optimization (Pure Optimization).
Fire Emblem HeroesStygian: Reign of the Old Ones
Axis by axis
Execution1 vs 2
Stygian: Reign of the Old Ones leans harder on execution: Turn-based combat needs no twitch reflexes
Reads2 vs 2
Even - both lean on reads about the same.
Variance5 vs 4
Fire Emblem Heroes leans harder on variance: Gacha summoning rolls gate which units you even own
Optimization7 vs 7
Even - both lean on optimization about the same.
Two games can score the same on an axis and still test it in very different ways - read each rationale, not just the number.