Keeper's Sack is a passive item added in The Binding of Isaac: Repentance.
- Gives Isaac stat upgrades when he buys items/pickups from shops.
- The three possible stat upgrades Keeper's Sack can give are +0.5 damage, +0.03 speed, and +0.25 range.
- Keeper's Sack will always give one stat upgrade when Isaac makes a purchase, plus one for every 5 cents Isaac spent on the pickup/item.
- Spawns three coins and a key on pickup.
- Store Credit: Anything bought will not give stats.
- Steam Sale: Stat boosts for every 5 coins spent will only apply to the modified cost after picking up Steam Sale rather than the original cost.