The Reaver drop is a technique popular in all three Protoss matchups. Building Reavers is a significant investment, which forces any Protoss player to maximize their damage output. The Reaver's slow movement can be overcome in combination with a Shuttle to increase the unit's mobility and shield it from damage. A Reaver-Shuttle combination can be used to harass an enemy base, for defensive applications or as part of the Protoss army.
Regardless of the usage (harassment or ordinary offensive unit), the Reaver will always be carried within a Shuttle: it will only be dropped to fire a Scarab onto a specific target. Targets are usually chosen in order to maximize the Scarab's splash damage upon other enemy units or buildings. To avoid losing the Reaver, it can be picked up into the Shuttle after firing each shot if needed.
Some techniques can be applied in all three match ups. A Protoss should consider the following characteristics of Reavers and their Scarabs, while adapting to the current game situation.
- Like all units, a Reaver attacks randomly if it wasn't commanded to attack a specific target.
- If a Reaver isn't picked up after a drop, it will keep firing at the designated target until it is dead
- The "Build Scarab" command will cancel the manual target selection: a Reaver will pick a random target again after new Scarabs are queued up
- A Shuttle's speed decreases as it approaches its target area, the Shuttle ought to be kept moving near the Reaver to avoid this.
- Reavers should be dropped while the Shuttle remains moving. This can be achieved by clicking on the wireframe of the Reaver to cause it to unload, or by placing the Unload command on top of the moving Shuttle. The former is recommended if other units are within the Shuttle.
- A Shuttle can be moved with the Patrol command. If the Shuttle is under fire, it will automatically retreat. However, this technique should be used with care.
- Often cheaper, weaker units such as Zealots are dropped before the Reaver in order to take fire for the more important Reavers
- A Reaver's Scarab is more likely to bug out if the Reaver was actually dropped behind Minerals. If the Reaver was dropped on top of Minerals and the Reaver ends up behind the Minerals, a Scarab is more likely to still hit and shoot "through" the mineral patches.
- A Scarab following retreating units, e.g. Speed Vultures or escaping workers, is often unlikely to deal any damage. In this case the Protoss can manually detonate the Scarab by selecting the Reaver and giving the Stop command. The Scarab won't deal any damage, but the Reaver will be able to shoot again sooner.
- A Reaver used to harass an opponent's mineral line should always be dropped in the most likely escape routes. The Reaver is more likely to focus workers moving from mineral line to mineral line, if it stands in their path.
Reavers are usually part of the early game against Terran. In most cases Reaver drops are used to kill the Terran, or at least to deal enough damage to gain a significant advantage. However, the Reaver is not limited to being a harassment unit only. Especially against aggressive openings such as Fake Double Builds or Two Factory Builds it can be used to thin out advancing Siege Tank lines. The only opening that efficiently counters an early Reaver drop is an early Vulture drop by Terran, or any other opening which allows the Terran to produce Wraiths early on.
Any Terran army will consist of mostly Siege Tanks and Vultures. If the army is still moving, meaning that the Siege Tanks are unsieged, a Reaver's longer range can be used to target down stray units, although the Reaver should be handled carefully.
If the Terran sieges his Tanks, the Reaver can be used to thin out the Tank line. In most scenarios, a Protoss will harass the Siege Tanks with two Zealots and one Reaver. The Zealots (one at a time) are dropped first, to draw the Tank's fire on them, the Reaver will be dropped shortly afterwards and will focus on clumped units. This technique is mostly a combination of Reaver-Shuttle Harass and Zealot Bombs. To avoid this the Terran may simply unsiege. Dragoons can be placed close to the set-up.
Siege Tanks have a rotation time. This means that it takes a few second for Siege Tanks to turn toward their target. This rotation inertia can be abused by the Protoss to minimize the likelihood of Tanks focussing on the Reaver after killing a Zealot. Doing this buys a few seconds of extra time to pick up a Reaver after shooting a Scarab.
Maximizing the damage
Scarabs traverse terrain in a rather complicated fashion. When they have a target set, they treat other units and buildings as obstacles and behave exactly like a melee unit when trying to reach its target. Once a Scarab comes in close vicinity to the target, it exlodes, dealing splash damage.
- Three Tanks, A and B are potential drop zones. The drop zone and the targets produce different outcomes
- Firing from A at Tank 1 will result in the Scarab exploding at x1, dealing a mere 100 damage to one Tank. Not the maximum efficiency.
- Firing from A at Tank 3 may be a better choice, but it will most likely explode at x5, only dealing lowered splash damage (or even no damage) to Tank 1 and no damage to Tank 2 at all.
- A - Tank 2 would be the perfect choice because it would most likely explode at x3, dealing full damage to all three Tanks.
- Now if drop zone B is chosen, firing at Tank 1 will land at x2 (100 damage), at Tank 2 - at x4 (100-150 damage) and at Tank 3 - x3 (300 damage).
Generally, if several units are adjacent, a Scarab should be launched in such a way that it slides along the edge of a unit in order to reach another one, illustrated by the picture below:
Red line marks Scarab trajectory, yellow arrow the desired target.
Push Break: Rear Drop
The rear drop is one of two ways to use the Reaver-Shuttle combination to destroy a Terran army. In this case it doesn't matter whether the Terran army is sieged up. Usually, the main Protoss army attacks the Terran, while the Reaver is dropped on the edge of its firing range in the rear of the incoming Protoss army. Ideally, the army will soak up the first volley of the push, while the Reaver targets clumps of units and clears them up as fast as possible. However, this technique works most efficiently against unsieged Tanks and an army in motion, since a Sieged Terran can manually target the Reaver more easily.
Push Break: Front drop
The front drop technique is the second option for a Protoss using the Reaver-Shuttle combination against a Terran push. This works best against a Terran with Tanks already in Siege Mode. The Shuttle is used as spearhead of the incoming Protoss army. Usually Zealots are dropped first and the Reaver is only dropped after the Terran army already shot its first volley. The larger a Terran push is, the harder this technique is to effect, as a vast part of the Terran army will be secured by Goliaths or Turrets.
Reavers are a staple unit in the Protoss mirror. While in PvT they are almost exclusively used to harass, in PvP they are a main fighting unit in early/mid-game. One of the most common PvP tactics involves getting 2 Gateways, a Robotics Bay, Shuttle, Observer and then Reavers, while continually increasing the Dragoon count.
In order to use Reavers in a battle where the opponent has Dragoons, the following techniques are used:
- Reavers are dropped outside of the enemy's Dragoon range
- Especially in later stages Reavers should be spread out, rathar than clumped
- The Shuttle should be constantly moved above the Reavers
- Opponent's Reavers
- High-tech units (Archons, High Templars)
- Clumps of units
- The most important part remains not losing the Reaver.
- As soon as Dragoons target a Reaver, it should be picked up in the Shuttle and droped again right away (if in a relatively safe spot) or flown to a safer location. Picking it up breaks the Dragoons' targeting command and dropping it quickly prevents them from shooting down Shuttle and Reaver together.
Shuttle speed remains the highest-priority upgrade, as it will also help your other forms of harass.
Over the course of a game Reavers usually lose value. They're easily countered by the High Templar's Psionic Storm, as the Shuttle and the Reaver are usually in the same spot. Once High Templar are fielded, Reavers are mostly used in drops.