ToME: the Tales of Maj'Eyal

I've found the Unknown Tunnels, and gotten trapped. Now I'm in the room with the merchant, who begs to be rescued. I've wandered, around encountered an alarm trap, killed the thugs, but I cannot find the assassin lord. Watched on Youtube that he should be next to the merchant, but there's nothing there and I can even walk into the square, that I cant do to other sometimes invisible thieves and assassins.

What's up? Can't I do anything, except use the rod of Recall or what it's called to get out?

Might be that I stood on that square while talking to the merchant btw...

Won't hitting/casting something in the square where the Lord is supposed to be fix it?

Threw a alchemist bomb, channeled the staff, even dug the square for 30 turns, but nope, he's not appearing.

Say guys, If I use my Rod of Recall to get out, can I get back in ever again?

I'd like to start a Rogue class, and use Poison, but haven't unlocked that yet. Being so close to uncloking it now, standing in the room where the chap should be...

No coming back once you leave.

It sucks but after clearing all Tier 1 dungeons, you can auto-explore and encounter the dungeon again with a new character I think. Shouldn't take very long. I've unlocked it using an archer, but anything should work really!

Yep, I did unlock it with a later character. Now that I have poisons, I haven't actually used it even once, despite having a level 29 rogue on adventure mode.