Assembly Line Fever
is a limited-time event where all Souls earned in Factory receive a 20% bonus. While the event is active, the assembly line runs at full speed: every enemy defeated in Factory drops more Souls than usual, helping you progress faster through your upgrades and goals.
You don't need to activate anything special: as long as you're playing in Factory during the event period, the multiplier is applied automatically. Take advantage of this window to farm Souls more efficiently before the event ends and the bonus disappears.