Playing with FiendFolio, by the way;
The blue chests can spawn in challenge rooms; and when opened, they do not start the challenge rooms.
They can also replace normal shop pick-ups... and can be opened for free.

Limbo Deals can also appear after the Mom's Heart fight on the Corpse route.
And in the hole room before the Mother boss fight.

Originally posted by White_Tiger:

Playing with FiendFolio, by the way;
The blue chests can spawn in challenge rooms; and when opened, they do not start the challenge rooms.
They can also replace normal shop pick-ups... and can be opened for free.

Limbo Deals can also appear after the Mom's Heart fight on the Corpse route.
And in the hole room before the Mother boss fight.

Ah, I definitely didn't test the later floors enough. I'll get working on a fix for those issues. Thanks for the report!

Some of the negative effects such as sandles dont stop after D4 the item away

Contract with ultra greed stopped working in the Mega Satan boss fight while playing as keeper. Was working with in the blue baby boss fight

Originally posted by SarahFox:

Some of the negative effects such as sandles dont stop after D4 the item away

Fixed! Also fixed the issues mentioned by White_Tiger in the first post (I think)

Originally posted by Bungus:

Contract with ultra greed stopped working in the Mega Satan boss fight while playing as keeper. Was working with in the blue baby boss fight

I intended for that item to never show up when you're playing as keeper, but I've realized that I didn't program the keeper and lost-birthright blacklists correctly. I'll fix that up as soon as I can.

The boss transition image and the floor transition image for Jahaziel are completely out of wack and are way too small/floating off the ground.

Empty Sack's fake pickups bypass Holy Mantle. Just lost a really good run when I touched one during Downpour mirror segment...

For me, even if I enter from the left or right of the boss room I always end up at the bottom of Limbo and the music stutters a bit when entering Limbo

(1) When I start the battle with Limbo Angel, the door is still open.
(2) Items that have already appeared but that I didn't pick up are likely to reappear the next time Limbo Room appears.

Originally posted by AaadyB:

The boss transition image and the floor transition image for Jahaziel are completely out of wack and are way too small/floating off the ground.

Yeah, that's an issue with porting the animation over from the previous version. I'll sort it out soon.

Originally posted by Fi-B:

For me, even if I enter from the left or right of the boss room I always end up at the bottom of Limbo and the music stutters a bit when entering Limbo

That's a side-effect of the method I used to spawn limbo rooms, not much I can do about that

Originally posted by yuqingzhitian:

(1) When I start the battle with Limbo Angel, the door is still open.
(2) Items that have already appeared but that I didn't pick up are likely to reappear the next time Limbo Room appears.

Right, almost forgot about those. I think the door actually does close, it just doesn't animate properly. Items re-appearing is a more difficult one to fix, but I'll take a look at it when I can.

Originally posted by Borko:

Empty Sack's fake pickups bypass Holy Mantle. Just lost a really good run when I touched one during Downpour mirror segment...

That's odd. I'll have a look at it.

Limbo deals not showing up when playing as tainted cain? like period?

Edit: Just got one, but only after getting off the mother path. Do they not spawn on alt-path?

Items of limbo pool not affected by chaos(they not replaced with items of other pools)

Also q0 and q1 items not getting rerolled by sacred orb

It just seems to not work for me, tried it with no other mods, tried it with APIs and other mods, nothing seems to work.

The character with the tainted version shows up, but no other content (the tainted version doesn't have the item for example, and nothing else shows up from the mod)

Guppy's Eye + Wings of Icarus. It seems like Wings transform objects after you enter the room (I assume that based on animation I see), while Guppy's Eye works based on objects before transformation. That resulted in me seeing coin inside fire place but getting nothing after destroying it. Even more - I still see small coin image after destroying this fire place.