Dad's Battery

Dad's Battery
Flavor text	"Energy debt"
Item Pool	Battery Bum Devil Room Old Chest Shop Shop
Quality	3
Item Tags

Dad's Battery is a passive item added in The Spitshine Update.

Effects

• Active items can be activated without needing to be fully charged. Doing so will convert the remaining charge that was originally required to activate the item into negative charges, and changes the capacity of the active item's charge bar to 12 for as long as there are negative charges.
  • Negative charge acts as dud charges that do not contribute to the actual charge of an active item, and must be removed in order to begin charging the normally item again. Negative charge can be removed in every way an active item can get normal charge, such as clearing rooms or collecting batteries.
  • If all negative charges from an active item is removed, the charge bar's capacity is reverted back to the amount the item originally had.
  • The maximum amount of negative charges an item can have is 12, and active items can not be used if the amount of negative charge that would be gained goes over this limit.
• Each point of negative charge on an active item will reduce Isaac's speed and shot speed, down to a minimum of 0.1 speed and 0.6 shot speed with a negative charge of 12.

Notes

• The speed down and shot speed down is calculated with the following linear interpolation formulas:
  • Movement Speed = (1 − (Negative Charge ÷ 12)) + 0.1 × (Negative Charge ÷ 12)
  • Shot Speed = (1 − (Negative Charge ÷ 12)) + 0.6 × (Negative Charge ÷ 12)
• Negative charge will persist across active items — switching the held item with another that has any amount of regular charge will add the amount of positive charges from the new item to the negative charges Isaac had.
  • Dropping or removing Isaac's held active item completely will similarly still retain the amount of negative charges, as shown by the charge bar next to the empty slot for Isaac's active item.
• Removing Dad's Battery while Isaac's active item had negative charge will remove the speed and shot speed down, and revert the held Active Item's charge bar back to normal amount. The active item will still keep a negative charge, however, and if the amount of negative charges was more than the capacity of the charge bar on the active item, then the number of negative charges will be reduced to fit.

Interactions

• Everything Jar / Esau Jr. / Kalu's Severed Head / Astropulvis: Blacklisted by Dad's Battery — These items can not be used when they do not have enough charge, and are unable to gain negative charges.
• Butter!: Activating an item that does not have enough charge with Dad's Battery will not cause the item to be dropped.

Gallery

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  Older versions of Dad's Battery, including a placeholder icon.