In Reforged, the unit's name is Sapper instead of Goblin Sapper.
Patch 1.10 (2003-07-03): Goblin Sappers now deal 750 damage to buildings, 250 damage to all units, and 185 damage to Heroes. These values are reduced by armor values such as '5 armor', but do not interact with armor types (e.g. 'Medium armor').
Patch 1.01 (2002-07-05):Can no longer be loaded into transports.
Battle.net Warcraft III - Neutral -> Units -> Goblin Sapper