Terrain Tilesets

[Deadtrollx]

Ive seen in some warcraft 3 maps that they were able to get more tilesets into their map than what is allowed into a warcraft 3 map. I was wondering how they could do that without the map editor telling them they are passing the limit? I wanna make a map where there's many tile set because of different areas of the map. Help would be appreciated. thank you!