A TX4 Piranha is a type of lightly armored combat scout skimmer used by the Tau Fire Caste - a mobile weapons platform capable of great speed and maneuverability. With its jet engines and anti-gravity engine, a piranha is a fast-moving vehicle that is extremely difficult for an enemy to hit, its twin crew is good at hugging the terrain and making the most of any cover. Additionally, a Piranha's armament allows it to strike well in excess of its own weight, either using its Burst Cannon to kill enemy infantry or using a Fusion Blaster to blast main battle tanks many times its own size . Along with a nose-mounted main armament, a Piranha carries two Gun Drones - either remaining on the vehicle to increase firepower, or put into AI (Artificial Intelligence) mode to carry out a different mission. As a solo hunter, piranhas are dangerous enough, but when used in teams, they become truly deadly.
The first time the TX4 Piranha was first encountered and identified by the Empire was during a diplomatic mission to the Tau Sept world of Dal'yth, where it was used as an unarmed diplomatic transport vehicle for water caste negotiators. However, during the Taros Campaign, the Piranha was first tested in a military application in the field, and was subsequently codenamed "Piranha" by the Empire.
During the Taros Campaign battle for Hydro Processing Plant 23-30, piranhas were widely used in support of Remote Sensor Towers already in the area for Seeker Missile support. This resulted in the 114th Cadian Regiment's relief column being constantly harassed by rocket attacks and days of fighting between Chimeras and piranhas. This resulted in the relief column being delayed long enough for the Tau Hunter Cadres to overrun the facility. Piranhas also played an important role in the desert warfare on Taros, harassing enemy forces with the support of Hunter Cadres and eventually pursuing the Imperial Guard's Tallarn regiments as they retreated to their landing zones in the closing stages of the campaign.
Since the Taros campaign, the Piranha has been upgraded in terms of armor and armament, and has proven to be a particularly successful support post for Pathfinder teams. A favorite of the Fire Caste since their introduction during the Second Sphere expansion, Piranhas have quickly proven worthy of praise. Spots in the Fire Caste's piranha training programs are highly competitive, and those who graduate successfully enjoy higher status among their comrades.
Piranhas are deployed in a variety of capacities, and formations range in size from single vessels to a team of up to five people working together. These agile vehicles have myriad uses within the Tau military: their speed and powerful firepower allow them to serve in roles as diverse as armored escort, reconnaissance troopers, tank hunt, flanking raids, supply line raids, mobile reserves, or even in extreme circumstances, sudden assassination.
Larger schools of these deadly gliders can use their burst cannons to annihilate enemy infantry units, while smaller formations are ideal for wiping out scouts or dealing with unexpected enemy troop deployments. Lone Piranhas armed with the deadly Fusion Blaster are skilled hunters of enemy tanks. Using its speed, the speeder attempts to maneuver to target enemy vehicles in their more vulnerable side and rear armor. During an attack run, piranhas are a motion blur, and the crew rely more on their speed and ability to dodge than any amount of armor. Using her jet engines and anti-gravity engine, the Piranha glides across a planet's surface, and her twin crew is well-equipped to adapt to terrain and make the most of any cover.