Here's a combination of different trolls from various manufacturers (I don't remember for sure which one is made by whom), starting with this interesting and quite tall chap.
As you can see, there's a wide variety of pose and personality to each sculpt, but I tried to keep them unified via color scheme and basing.
There were a few basic elements to that color scheme, and the basing was kept unified by utilizing the same type of bulletin board cork and the sculpted mushrooms.
The Vallejo Environment Moss paint created an interesting color/texture effect on the rocks and mushrooms which contrasted nicely with the muted, cool grays.