Making a exploring stage

[Shawnthesponge]

I want too make a level where the player runs around and enters a stage like in StH 360,unleashed and SADX. how to make it

 

[daiches99]

Just have a simple stage with a few exit sectors with custom exits.
http://wiki.srb2.org/wiki/Exit_Sector
http://wiki.srb2.org/wiki/Linedef_Type_71