RE: Show us your Terrorgheist
Uthiliano, try getting the warhammer basing kit. Its expensive, so you might wanna try and get it cheaper of ebay or something, but it really helps alot. It comes with 2 tubs of slate (medium and large) a tub of resin basing details, and a tub of pretty much entirely resin bases, as well as a brass sheet of leaves.
Most of my fantasy bases consist of first gluing on a few bits of medium slate (rocks)(undercoat black, drybrush codex gray), then I glue on some small slate (which only comes in the 40k kit, but sand does pretty much the same thing) painting the small slate (or sand) as dirt (undercoat black, drybrush scorched brown, drybrush graveyard earth, add devlan mud) then when the whole mini is painted, I add scorched grass flock to any area I didnt cover with dirt/stones.
I also add the occasional resin bit from the basing kit or just skeleton bits here and there throughout the unit to create objects of interest.
You can also base the occasional member of the unit on top of a large piece of slate to create height differences if you wish.