here is link for bb mod download it and then u can see what the modder sees its cool too, stuff is added on like wood on the base stacked up, up on the cliffs wood and teleporters, and in the middle on top a gun room with all guns INCLUDING NEEDLER (which shoots out heat seeking rockets)
http://halo2.filefront.com/file/Halo_Trial_Battle_Base_Mod;70011#Download