Forge version: 36.1.32
Twilight Forest version: twilightforest-1.16.5-4.0.490-universal.jar
Link to crash log: No crash

Steps to reproduce:

1. Defeat Naga
2. Take one scale
3. Enter Tower lich and go to top
4. No twilight lich is there.
   I did it on 2 lich towers but no boss at all.

What I expected to happen:
Have a boss in order to continue on progression system

What happened instead:
Nothing has poped. No boss. I am stuck in progression system

Is there a way to pop this boss ? (asking an admin of this server to give me an egg ?)
Is it something I am doing wrong ?
Is it possible that for any reason, the boss unpoped because of an upgrade and then it will never pop again ?

Thanks for your help,

DiabolosMan

oh yes, we upgraded from an older version. So maybe it is the reason..... Thanks for the tip. We will try to delete the entire dimension and let it regenerate

glad to help! Have fun with the mod!

if youre on a server, then someone most likely already defeated it. You'll probably have to find a new tower

It is on a server, we are 3 on it, I am the only one in the twiligh. So no, nobody defeated it.... Moreover, no torch, no hole, chest full of loots.... So I confirm I was the only one and the 2 other guys confirmed not in twilight

the other reason could be if you ever upgraded TF from 4.0.435 to a newer version. Some code was changed making it so spawners that already existed in loaded chunks would disappear. You can still find fresh spawners in unexplored areas.

Thanks. For information, it worked. The admin deleted the entire twilight forest dimention and when I went again, same generation (because same seed) and did again the lich tower. On top, the boss was there ;-)