According to simulations run on different futures of Ignis and humanity, Revolver says that Lightning's is the only one that leads to mutual destruction.
You’re the one who’ll 
see hell, Light Ignis!
Du wirst in den Schlund
der Hölle blicken, Licht-Ignis!
¡Eres tú el que visitará
el infierno, Ignis de Luz!
Você que vai ver o inferno, Ignis da Luz!