Tentative unofficial 1.666 changelog for the Eternal Edition. ( HARD MODE CHANGELOG ON REDDIT )

[Choco]

EDIT : THE FULL CHANGES TO HARD MODE CAN NOW BE FOUND HERE : http://www.reddit.com/r/bindingofisaac/comments/34o6gu/complete_list_of_changes_in_hardmode_besides/

Since there aren't any patch notes yet, I'm going to list all the changes I have found so far. Feel free to contribute by adding the stuff you've found.

Note that this covers everything from 1.48 ( the previous Steam version of WotL ) to 1.666 ( Eternal Edition ), so some changes might be redundant with the 1.50 version ( non Steam )

Global changes

• Hard mode added ( shows a white pentagram on the bottom left corner of the screen in game )
  
  
• New Steam and in-game achievements added
  
  
• The size of the health bar now scales with the number of heart containers ( i.e. you can now see the heart containers you have past 12 ), up to 48 visible hearts.
  
  
• The amount of Kamikaze Flies you can keep between rooms is no longer limited to 5 ( the maximum seems to be 10 now )
  
  
• Shot speed up/down pills added
  
  
• Explosive Diarrhea pills are back in the game
  
  
• You can no longer leave a room if there's a black fly in it ( you can't exploit flies to reset a room or turn a slot machine into a fortune teller anymore )
  
  
• Dying in a boss room after clearing it doesn't cause the boss to respawn anymore
  
  
• Killing Mom's Foot ( Depths/Necropolis 2 boss ) can now reward the player with Mom's Purse
  
  
• Wiggle Worm is more dynamic and allows the player to angle shots
  
  
• The Parasite got tweaked to no longer hit the same enemy twice with one shot
  
  
• Mask of Infamy now has a health bar
  
  
• Hoppers and Keepers got their movement speed increased and can now jump over obstacles
  
  
• New trinket, the Game Squid, added : gives a chance to slow enemies on hit
  
  
• Eternal Flies now stay white when their host is destroyed ( their interaction with familiars might also have changed? )
  
  
• The Habit now gives the amount of charges you'd get for clearing a room instead of a flat 3 per hit
  
  
• New room patterns added
  
  
• Item pools changed ( some items might not be special anymore, some that weren't now are )
  
  
• The Crystal Ball now removes any active Curse of Darkness when used
  
  
• New monster added : a ball of flies that looks like a double Moter
  
  
• Mom's Contact now also reduces shot speed
  
  
• The Mask + Heart monster's health has been reduced
  
  
• Magic 8 Ball now also shows the location of the Boss Room on the map
  
  
• Basement/Cellar XL item rooms have a chance not to be locked
  
  
• Using the Joker card can fail to send the player in the Devil Room and instead teleport the player in a random room or do nothing at all ( probably only happens in Sheol, the Cathedral and the Chest )
  
  
• The Candle cannot hit offscreen enemies anymore ( like the doors in Mom's fight )
  
  
• Teleport! ( the active item ) now has a chance to send the player to the I AM ERROR room

Hard Mode only changes ( see the Reddit link above for details )

• New white champion version ( eternal? ) of bosses and enemies added : they have new attacks, increased health and can drop Eternal Hearts ( only a chance for normal mobs, guaranteed for bosses )
  
  
• New challenge room added ( Eternal challenge ? ) where you can fight several eternal enemies and bosses for an Angel Room item
  
  
• New transformation added, Eternal, that gives you flight (and damage?) if you get 7 health upgrades from eternal hearts
  
  
• Rerolling an item with the D6 can fail and make the item disappear ( based on luck, see the Reddit link above for the formula )
  
  
• Orbitals ( Cube of Meat, Pretty Fly etc ) now disappear after a few hits, but reappear after leaving the room
  
  
• Bomb pickups can turn into troll bombs when touched ( based on luck, see the Reddit link above for the formula )
  
  
• The chances of getting a reward after clearing a room are lower ( based on luck, see the Reddit link above for the formula )
  
  
• The drop rates from champions are lower
  
  
• The player's damage is lower in hard mode ( see the Reddit link above for the formula )
  
  
• The chances for a special item to appear have been tweaked ( check Reddit for the formula )
  
  
• Brimstone, Dr.Fetus and Epic Fetus appear less often
  
  
• Horsemen and some alt versions of bosses can be encountered even if you don't have the corresponding achievements unlocked
  
  
• Guppy's Paw now gives 2 Soul Hearts per Red Heart instead of 3
  
  
• The Sun card and the Full Health pill only heal you for a few red hearts instead of fully
  
  
• Red Heart container cap increased to 16

To be confirmed

• Conquest ( and Headless Horseman?) can now drop a Cube of Meat
  
  
• My Reflection may have changed ( tears seem to follow a fixed path instead of being affected by shot speed )
  
  
• Rusted Key now works as intended

[Trib3n]

Has someone experienced a D6 rerolling fail in normal mode ?

[Fechdog]

I just beat Blue Baby's hard mode in the Chest and the thing for unlocking Eve's bird foot appeared as if it was the first time I beat the Chest with Blue Baby. Anyone else experience this?

[Choco]

Originally posted by GPDM:

Has someone experienced a D6 rerolling fail in normal mode ?

I've played a quick Isaac run in normal difficulty and haven't experienced any item disappearance, so I guess it's exclusive to Hard mode.

Originally posted by Fechdog:

I just beat Blue Baby's hard mode in the Chest and the thing for unlocking Eve's bird foot appeared as if it was the first time I beat the Chest with Blue Baby. Anyone else experience this?

It has already happened to me in the past. Have you cleared your cache and cookies ( with CCleaner or something like that ) recently ? That's most likely because of that.

[Trib3n]

I have also noticed that IPECAC is really weaker than before (hearts not killed with one shot for example and Isaac is far more difficulte to kill with IPECAC for example)

[Soulless]

Thanks for the update list. Already suffered from various points on that list, specially the "Eternal" versions from most of the monsters, certain bosses are massive pain; last I´ve encountered was Super Gluttony accompanied by a normal Gluttony, was tortuous.

[atro city]

The Horsemen are also a colossal pain now. Haven't fought War and Death, but Famine and Pestilence are ridiculous. Conquest isn't much different, but he's Conquest, so he's already a ♥♥♥♥.

[Choco]

Originally posted by atro city:

The Horsemen are also a colossal pain now. Haven't fought War and Death, but Famine and Pestilence are ridiculous. Conquest isn't much different, but he's Conquest, so he's already a ♥♥♥♥.

Eternal War is broken as hell. He spawns a ton of Globins instead of troll bombs when he flies across the room and killing him can be tedious.

[Stealth]

I noticed that in hard mode I get less drops after clearing rooms like it is in hard mode of Rebirth.

[Stealth]

Originally posted by Choco:

Eternal War is broken as hell. He spawns a ton of Globins instead of troll bombs when he flies across the room and killing him can be tedious.

Agreed. I luckily beat him because I had homing Ipecac but it was hard anyway.

[Choco]

I added some new stuff to the list

[Choco]

Updated again.

[PMBall]

It seems that the maximum amount of hearts that can be seen es 48. Beyond that you have to guess how many there are, but its still a decent number

[Choco]

Originally posted by PMBall:

It seems that the maximum amount of hearts that can be seen es 48. Beyond that you have to guess how many there are, but its still a decent number

Alright, thanks.

[[*GRS*] Darkhar]

The Dead Cat bug (wich allowed to respawn a boss if you killed yourself in the boss room after deafiting it, getting another item) is now fixed. Will miss those 8 items at a floor.

[Choco]

Originally posted by *GRS* Darkhar:

The Dead Cat bug (wich allowed to respawn a boss if you killed yourself in the boss room after deafiting it, getting another item) is now fixed. Will miss those 8 items at a floor.

Thanks, added.