Expansion Pack is an unlockable trinket in The Binding of Isaac, added in the Repentance DLC.

When Isaac uses an active item, the effects of another random active item are activated in addition to the original item.

Can only grant active items that have a charge time of 1 or 2 rooms.

Timed recharge and infinite use items will trigger the effect only once per room.

This page shows information as of the latest Repentance release.
To see latest up-to date information about this trinket for the new Repentance+ (Online Co-op) DLC, check this page instead.

Defeat Isaac, ???, Satan, and The Lamb as Tainted Bethany.

The following special synergies and interactions for Expansion Pack have been documented.

* Note that not all possible synergies and interactions are listed here.

• Check out the trinket description on the external Isaac Wiki.