Seeing Double is an unlockable challenge in The Binding of Isaac, added in the Repentance DLC.

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

20/20
20/20 (P2)
X-Ray Vision (P2)

Note: this list does not include characters' default starting items.

All enemies and bosses are doubled.

The following is unlocked for completing the Seeing Double challenge: Broken Glasses

Defeat Mother for the first time.

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