Why lowering enemy Initiative boosts all your fire damage

Because of the stat triangle: fire damage is reduced by the defender's Initiative. So if you break enemy Initiative, all your fire goes up at once — for the whole army, not just one dragon.

The Initiative debuffers in the roster:

• Jagadrix (*Sly Whispers*): −Instinct AND −Initiative, and at 10★ he sticks the debuff on the enemy with the highest Instinct until the end of the fight.
• Crimson (at 10★, on even rounds: −Instinct/−Initiative).
• Shadowsong *Trap* (habit: −18% Inst/Init).

That's why Jagadrix is the universal enhancer: he breaks two defensive stats at once (Initiative → +fire, Instinct → +physical and −enemy tactical). Put him in your main army.

The general logic of stat debuffs: lowering one enemy defensive stat = multiplying one damage type for your WHOLE team. That's the lever most players miss.