Two things. One: You should go do Priest In Peril and any other quest you need to do to get into Morytania. Then venture into Mort'ton. There are several shades, and you get prayer exp and colored metal keys for burning the various corpses. However, you need to have done at least part of Shades of Mort'ton quest to burn them. Loar shades hang around outside the tomb, higher lvl shades requiring higher level pyrelogs to burn hang around inside the nearby tomb which can be opened by any metal colored key(such as bronze key red). There are chests inside the tomb that can be opened by these keys as well, that have various prizes inside them. Two: If you've done Mourning's Ends part 2, you will notice lvl 74 shades like to lurk inside the elven light temple... i thought the light temple things where called shadows in either form