37:Floor_MoveToValue(tag, speed, height, negative, change)
68:Floor_MoveToValueTimes8(tag, speed, height, negative, change)
Moves tagged floors to a given absolute height value. Speed is number of eights of map units per tic (8 is the traditional Doom floor speed). If negative is 1, the -height destination will be targeted instead. Change specifies whether to change floor texture and/or effect.
Floor_MoveToValueTimes8 is like Floor_MoveToValue except that the destination is actually ± height x 8. Both this special and the negative parameter are artifacts of the Hexen map format, used mainly by ZDoom when it introduced or extended these specials. Under UDMF, ACS or ExtraData you won't need to use either the negative parameter or the Times8 special.