In the corrupted temple quest I found the second part of the diary of some Idras Tombelthen guy that says something like he left something hidden in a rock formation in a clearing. So he left these notes so that his family can eventually find this place.

Well, there are several rock formations in the temple area and I searched but couldnt find anything. So, is this similar to the Ankheg armor thingie in BG1, that it was very difficult to find and you just had to roll over the mouse again and again till you found it? Anybody know?

Ok, regarding the Shadow Dragon... I think it is too tough for me right now, so can I come back and kill him later???

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the bit of journal is only of use if your main character is a ranger - it's to do with one of the quests you do as part of the rangers stronghold. i wasted time looking around myself - most annoying - but it was completely useless for me as my main character is a sorceror.

as for the dragon, yeah - you can comeback later and kill him. i assume anytime would be fine but i killed him towards the end of chapter 2.

try keeping the ward stone on you as you attack him, set everybody up around them(haste them and chant/bless) and use any spells that attack undead or chaotic evil creatures..I think holy word works pretty good. Should kill em without too much damage.