function AddSpecialEffectZ takes string modelName, real x, real y, real z returns effect
//Creates a invisible platform at the given x/y/z coordinates.
local destructable d = CreateDestructableZ('OTip', x, y, z, 0., 1, 0)
//The created special effect will now appear on top of the platform.
set bj_lastCreatedEffect = AddSpecialEffect(modelName, x, y)
//Removing platform and null the variable. The effect will still keep its height.
call RemoveDestructable(d)
set d = null
//Return effect.
return bj_lastCreatedEffect
endfunction