The following section contains information from a previous version of StarCraft II which is no longer valid.
Concept art for reapers exists at least as far back as 2005. Most of these concepts correspond to the idea of a jetpack-wearing terran equipped with duaol weapons. One however, depicts the reaper armed with a single cannon weapon, with micro-missiles held alongside its jets.
Reapers were produced from the merc haven at BlizzCon 2007, using a different technique than other terran infantry units. The haven housed up to four reapers. The entire supply could be bought at once, with the supply recovering over time. Reapers could be built very quickly. However, this was later changed with reapers being built at the barracks like other infantry units.
Reapers previously could not jump up a cliff without vision on the high ground, the medic's optical flare was an early game method of enabling reapers to do so.
The reaper throws a demolition charge on the ground; two seconds later, it detonates, damaging friendly and hostile ground units and buildings in the vicinity. A red timer bar shows how long until it detonates.
The mines deal 30 damage + 30 against armored units and buildings. Mine explosions do not detonate other mines and do not deal damage to burrowed units unless the player can detect them.
The mines are very small but visible. They can be hidden by units moving past them.
↑ 5.05.15.2In the current build you cannot destroy D-8 Charges. By that I mean that you can select them, but they are indestructible (they don't have HP like other units do, just like units caught by Arbiter's Stasis Field in SC:BW for example). If you are playing against Reapers though, you can still dodge the charges, as it takes them around 2 seconds to blow up. Kapeselus. 2010-01-29. Reaper Charges. Battle.net StarCraft II Gameplay Discussion Forum. Accessed 2010-01-29.