I've got two new questions :

<span class='standouttext'>Spoiler : </span><span class='spoiler'>Has it influence on the story if I just use the exit and don't open the Lava hatch ?

And is it normal that the ancient stone-biter bites you ?</span>

When you find a big kettle of crazy, it's best not to stir it.
--Dilbert cartoon

"Interplay.some zombiefied unlife thing going on there" - skavenhorde at RPGWatch