How to set creepers's wave?

[xav]

All is in the title.
When i edit a map, there is not creepers wave.
How to set that?

[ficolas]

editing control.lua, its located where the map is. I cant tell u more atm.

[FreeER]

if it's not there copy the freeplay.lua from the lualibs folder into the save/scenario folder and rename it control.lua that should work