I think the puzzles were absolutely wonderful, maybe except two or three that were really without any clue at all.
The Iron Door with the red gem was the worst for me, I just didn't figure out that one, had to google it up. And then it wasn't the typical facepalm, I was pissed. So random. Bad devs, bad.
Also there was a grate in lvl 6 or 7 with some loot behind it that opened only by throwing a switch that a) was quite far away b) already belonged to another nearby grate. Mean.
As for the bone amulet - that was cheeky, I seriously didn't expect to use an item from lvl 3 on lvl 10. Luckily I didn't throw it away.
And as for the Tear of the Land, there's a rock a few steps away, together with some Toorum's notes. Maybe it's in a secret room, don't remember, but it was a relief for me, I got rid of my rocks long time before that. I thought the devs weren't THAT cruel
