Add Terrain Data


I tried to add terrain to my envi-met model, but the warning said “Only one terrain object will be consider”.
What should I put to my grasshopper process, to make sure all terrain object to be added.

I used Brep, Cap Holes ex, DF Envi-met Terrain, DF Envi-met Spaces.
And each brep contains one or multi surface, from rhino model.