How often do and what determines when Orodruth spawns?

[protopulse]

Been playing smithing characters lately and saw in a few logs of a mention of Orodruth, which is a unique forge. Haven't seen it yet in any of the games I've played.

So I have to wonder what determines if it spawns at all? And what depth should I scum for it if I want to see it?

[Pete Mack]

It occurs 1 in 10 enchanted forges, and enchanted forges have a roughly 1% higher chance of occurring every dungeon level deeper. So there's roughly a 2% -- actually 1-(.999)^19 -- chance of Orodruth on dl 19. It is pretty rare.

[protopulse]

Ah, no wonder I haven't seen it yet. I guess scumming 950 feet is my best bet then.

[Pete Mack]

But there's an 84% or better chance it occurs earlier. If it does and you miss it, it will not regenerate.

[protopulse]

84%? Where did you get that number?

Actually, how does forge generation work? 1 in 10 enchanted forges is Orodruth. How many percent of forges are enchanted? How often do forges spawn?

[Pete Mack]

edit: my bad. 16%, not 84%.
16% = 1-.999^(18*19/2)
The cumulative probability for Orodruth over levels 1-18. The same calculations work for enchanted forges, except using .99 instead of .999

[protopulse]

Do you know the probability that Orodruth spawns on each level? Say level 1 (50 feet) versus level 19 (950 feet)? It's easier for me to understand if you explain it to me in those terms.

[Pete Mack]

An additional 1/1000 roll on each level, so 1/1000 at level 1 -(999/1000)^2 ~ 0.002 at dl 2, etc, up to 1 - .999^19, just above the throne room. If you visit levels twice, there's a chance it will show up each time, so that increases the odds.

[protopulse]

I see. Okay thank you.

[captnamazing]

i saw it once man

it was fuckin awesome

i crafted some stuff

then i died