Athletics skill increases speed, strafing, side step length and improves your chance to dodge while attack simultaneously.  Thanks Devildog for the tip.

The Fiend of Ghazbu at the Tomb of Lost Souls always drops the rarest nether item, dried homonculus.  Great if you need one and can't find it. 

In the inner sanctum, the different color glyphs act as a key and are on display in the gated off room. Get (step on the glyphs to activate) the colors in proper order and the door opens.  Thanks EL for the tip.

Using Rat's tail and Bone Dust you can make a Summon Rats nether spell useful in the opening part of the game.  Thanks Spizz for the tip.