No vision penetrates the darkness of the orb, it's as if you are looking into nothing.

Randall remembers hearing tales of some of the earliest chosen agents of some gods that used orbs, black in color, that would negate or erase things they came into contact with.

Randall:

”Don’t let it touch you,” warns Randall, “It could be a powerful artifact of negation that erases your existance.”

Zenodor stands well clear just in case it starts to move erratically. "Fascinating. I wonder why this is here. Perhaps it is serving some specific purpose?"

Getting slightly distracted by his thoughts, he muses:

"Such a phenomenon sounds very dangerous , but could be quite useful for some purposes. It would create an elegant way to rid the land of things like cursed artefacts... or dangerous items like a lich's prophylactery"

"But what will it touch if left untouched, what would it erase?" Pepin says "should we try to destroy it?"

"Could we even destroy it? If it absorbs and destroys everything, it would surely just destroy any weapons we use. Maybe magic might harm it, bit I doubt it unless we use extremely powerful high-level spells. Perhaps we should just observe it and see what happens "

(You said it was moving towards the stairs but didn't reach them this turn. And it came out of the trap door, right? So I presume it is slowly but steadily progressing. Can we just follow it at a safe distance to see where it's heading and what it is doing?

We should probably also check where it came from, ie that trap door. We could split up, or we all go one way and send Irraxan (familiar) and similar the other way.)

The stairs are in the center of the room and the black orb drifted lazily out of the trap door once it was opened, moving very slowly toward the stairs. It is about halfway to the stairs.

You can follow it at a safe distance because you all move way faster than it.

Let me know if you all decide to split into two groups, who is in each group etc.

Tempe stays away from the orb whispering "I hope, this is not the thing that attacked, the scout earlier" he follows the group

As Temp moves to follow the group the black orb changes direction on a dime and begins to slowly drift towards him.

Tempe flies backward and up, full speed, while thinking move the other way.

Make an INT (Arcana) check.

The black orb continues to slowly drift toward Tempe. It only moves 10 feet. Now it is 20 feet from you.

What are my options? Terrain and such, did we take five since my last wildshape?

I believe everyone came down the staircase into this room with door, the hatch (where the black orb came from), and the arcane writing on the walls. The black orb has moved 10 feet toward Tempe. Everyone can post actions or discuss further (this is not on a clock of any sorts, but it still has to be dealt with in some way).

Randall:

Moving over and casting Guidance on Tempe, Randall asks, “Does someone have a spell or effect that might push the sphere back to where it came from?  I don’t know if telekinesis might affect it, but we could try.”

Tempe summons Pinky, and does his fiery teleport past the black orb and runs back too the hatch, hoping to find someway, to contain the thing.  

Zenodor & Pepin can post their actions before the black orb moves again. It has only been moving 10 feet at a time.

Pepin wonders if he should attack the orb.

"you guys sure we shouldn't try and destroy it?" 

Z moves backwards to avoid being too near it and tries a Telekinetic Shove (action) to see if he can affect the sphere to push it away. ["The target must succeed on a STR save (DC 18) or be moved 5 ft. toward you or away from you." - but I'm not sure if the thing is a valid target]

In reply to Pepin, he says: "I could cast a Forcecage around it. But I am not sure if it would hold really whatever this thing is. And even if it does, it would only help us for an hour. And I can only cast that spell once. So perhaps we should leave that option for last, if we need to escape it."

(ooc: this thing is currently controlled by something with a +19 bonus, so it auto saves vs. DC 18. This thing is hard to get control of and probably even harder to maintain control of.)

You have time to plan if you want as you can easily stay more than 10 feet away from it, it can only move 10 feet a turn.