Devil deals and seeds.

[Lord Seaendithas]

I had played a run where I had moms knife, brimstone and sacrificial alter in the cellar 2 devil deal. I later returned to the seed (VL8M JWPY). The items in the item room were the same, boss items the same and drops were the same. Even the devil deal was almost same. (Moms knife and sac alter) Except this time brimstone was replaced with the mark. After trying the seed a few more times it was still the mark. How could this be?

[Nazemec]

Brimstone is a special item, maybe you got lucky on the first generation and got it instead of the Mark (which would be normal generation)? Especially considering that Mom's Knife is a special item too, so Brimstone is even less likely to be generated afterwards (or the knife if generated in the other order). Just a guess.

[Ardenian]

Originally posted by Nazemec:

Brimstone is a special item, maybe you got lucky on the first generation and got it instead of the Mark (which would be normal generation)? Especially considering that Mom's Knife is a special item too, so Brimstone is even less likely to be generated afterwards (or the knife if generated in the other order). Just a guess.

Does it matter how likely it is which item is generated? OP got Brimstone with that seed, so shouldn't the very same items under the same circumstances spawn again? Are there more factors than just putting in the seed that determinate which items are in devil deal?

[Nazemec]

Originally posted by Ardenian:

Originally posted by Nazemec:

Brimstone is a special item, maybe you got lucky on the first generation and got it instead of the Mark (which would be normal generation)? Especially considering that Mom's Knife is a special item too, so Brimstone is even less likely to be generated afterwards (or the knife if generated in the other order). Just a guess.

Does it matter how likely it is which item is generated? OP got Brimstone with that seed, so shouldn't the very same items under the same circumstances spawn again? Are there more factors than just putting in the seed that determinate which items are in devil deal?

Maybe the order in which you see them could affect it (because of their "special item" status). To test it out, you'd have to do the exact same things in the exact same order. Only then it should be derterministic.
Again, just a guess.

[Ardenian]

Originally posted by Nazemec:

Originally posted by Ardenian:

Does it matter how likely it is which item is generated? OP got Brimstone with that seed, so shouldn't the very same items under the same circumstances spawn again? Are there more factors than just putting in the seed that determinate which items are in devil deal?

Maybe the order in which you see them could affect it (because of their "special item" status). To test it out, you'd have to do the exact same things in the exact same order. Only then it should be derterministic.
Again, just a guess.

Hm, I see, I hoped there was an easy explanation, as a seeded run should always yield the same results, unless there is a factor like taking no damage, no taking more than a certain amount of damage and things like that that determinate or change which items are in devil deal.

[Tato]

Since Mom's Knife and Brimstone generated, the special item rule applies which reduces the chance for subsequent special items. I guess Mom's knife was seen by the game first, which applied the 50% reroll chance to Brimstone.