Eve starts with a small health pool and great speed, only matched by Cain. She has the lowest base damage but this can be increased by taking damage, which activates the Whore of Babylon effect upon reaching 1 Red Heart. Eve is rather lackluster without the offensive boosts provided by her unique starting item, so the Whore of Babylon is what allows players to fight more effectively.
What you're going to want is to have your main starting item, Whore of Babylon, become a permanent bonus, which can be done by bringing your Heart Containers down to only half a heart remaining, then amassing Soul Hearts (Book of Revelations comes in handy, Guppy's Paw is even better if you can obtain it). Then spend regular hearts on Blood Donation Machine or deals with the devil until you get to a cursed mode, greatly increasing damage.
Another solution (Wrath of the Lamb only) is to use Guppy's Paw for all of your hearts, giving you technically zero Heart Containers, but giving you a permanent Whore of Babylon and a good lot of Soul Hearts. Consider Dead Bird as a bonus, don't get hurt specifically for it to spawn as Eve (like Cain or Judas) is a very fragile character initially, and you must do your best to conserve health in order to survive. In Wrath of The Lamb, The Polaroid is useful, as well as necessary to access The Chest, as it grants a shield for 5 seconds when the player is reduced to half a heart. This means that when in the Whore of Babylon state, the player will also be invincible for 5 seconds at a time after taking damage no matter what (especially useful if using Guppy's Paw).
Items that take Heart Containers away from Eve are ironically good items as they can help her to get into the Whore of Babylon mode. Items that grants Soul Hearts are also useful as they can keep Eve vital without getting out of Whore of Babylon mode.
- Guppy's Paw
- IV Bag
- Blood Rights
- Razor Blade
- The Nail
- The Pact
- Book of Revelations
- The Relic
- Dead Cat
- Ankh (permanent Whore of Babylon state after death)
- The Polaroid (Although necessary with every character to access The Chest, it is especially useful combined with Whore of Babylon when on using Soul Hearts)
- Mom's Pearl (Increases the chance of Soul Hearts spawning instead of normal hearts, pairs well with the Mitre)
Items that trigger on damage are good on Eve as well. However, since they usually take away Soul Hearts first, they are generally less useful.
- The Book of Sin
- Crystal Ball
- Black Bean
- Super Bandage
- Sacred Heart
- Bloody Lust
Items that heal Red Hearts for Eve are bad for her, if the player is aiming for a Whore Of Babylon-focused playstyle.
- Blood Bag
- Yum Heart
- Little C.H.A.D.
- Charm of the Vampire
- Magneto (Can drag hearts to Eve, making her accidentally pick them up)