Zenodor also uses his ability to directly see through his familiar's eyes. Just in case that makes a difference.

Also, Zenodor has an idea: He could cast "Darkness" on himself or Irraxan. Presumably monsters or people cannot easily tell (normal) darkness from magical darkness at a distance so would not notice. We could then first more Z&I and then the entire party into the bend, covered in darkness (Z and Irraxan can both see in magical darkness, so can lead the party). Z and Irraxan can observe whatever is around the corner, and then make a decision on how to proceed. If the whole party is there and ready, if necessary we can do a surprise charge out of the darkness (which can be dismissed if necessary) at whoever/whatever is on the other side.

Zenodor sees the same things Irraxan saw. Only 2 shadows are playing against the wall and they each have tentacles.

Zenodor hears the same things Irraxan heard. Way more footfalls than what you think 2 creatures should make.

If 2 or more other party members agree to the darkness/surprise plan I'll proceed with the encounter. It's also perfectly fine if someone wants to add or change some part of it, in which case I'll wait until everyone can post or have a say.

I'm fine with the plan, although I won't be able to see in the darkness so will stand still in it until it is dropped so I have a clear view again. 

Tempe has a look sadness as he quietly suggests "If you do this darkness on your familiar I can send my spirit to see what kind of danger these creatures really are but your familiar will have to watch far enough away to see what happens. And so mine can see."

ooc: Note I cant see thru my wildfire spirit.

Randall:

”Scout ahead in darkness if you like.  I am better suited to the light and ill-suited to stealth in any case.  I will stay back at the tunnel opening,” responds Randall, glowing mace in hand.

Are you planning on having your wildfire spirit go ahead of the darkness?

If so, trying to be stealthy?

Or openly entering by itself?

(Details of final plan necessary before continuing as I won't be doing any retcon if something is forgotten or left out.)

Ok. So just to return to the main thread, I think the agreed plan is:

Z casts darkness on Irraxan. Irraxan them creeps forward enough to see around the corner through the darkness, observing from a distance at what is making all those footfall sounds. 

Pinky will also use the darkness as cover and try to get closer in, pretending to be a random minor elemental and observing up-close.

(Perhaps the footfalls are more villagers appeasing/calming some tentacled creature? Last time the Plants were not attacking anyone until the natives ran (and stopped their music). Probably worth having a look)

The main party does not attack for the moment but stays in the darkness (or just behind, for religious reasons) ready to unleash hell if necessary - depending on what the little imp and sprite find.

Pinky will hide in the darkness till Irraxan thinks it safe enough to stop  and observe with pinky still moving forward out of the darkness towards the creatures with Z's blessings Stealth 4

We could follow behind the darkness while this is happening. Note the darkness spell is a 15ft radius effect so it has a total 30ft circle centered on the object you cast it on.  Anything listed as radius is 360 distance from its center

The party goes around the corner and Pinky flies out of the darkness. Pinky, Irraxan, and Zenodor all see a couple of strange looking large creatures with four legs, 2 claws, and tentacles. They stop moving about and turn toward Pinky.

Can Irraxan (or Z through his senses) see what might have caused all the other foot falls we heard?

It was just these 2 creatures, since they have 4 legs each and they were moving around in some sort of peculiar fashion, the number of footfalls exceeded what 2 humanoids could be expected to produce. Plus, at the end of each leg their foot/hoof appears to be split in two so there were as many as 16 footfalls minimum.

Pinky moves towards the creatures without a care.

(maybe everyone should roll initiative)

Well if you insist:

Bow initiative: 11

Petcan initiative 15 

14Initiative

There goes our carefully planned surprise attack. 

Initiative 6

Zenodor and Irraxan will stick together at the back, keeping the magical darkness spell. (which gives disadvantage to anyone trying to him Z with an attack - assuming they even know where he is in the first place) 

Brother Randall’s Initiative:  20

Tentacle Monster 1: 6

Tentacle Monster 2: 16