iel-Tan is located towards the southern rim of the galaxy, at the edge of what is believed to be the extent of the ancient Eldar empire. Amongst the Eldar, the Biel-Tan have a well-deserved reputation for being warlike. Their name means 'Rebirth of Ancient Days' in the Eldar tongue and it is the Biel-Tan who have taken it upon themselves to strive to rebuild the glory of the Eldar. To this end, the Eldar of Biel-Tan place greater importance upon the Path of the Warrior than other craftworlds do, for they know that if a new Eldar empire is to be forged, it will be done in the heat of battle and with much bloodshed.

The assembled warhost of Biel-Tan is known as the Bahzhakhain, meaning the Swordwind, or Tempest of Blades. The Swordwind relies on a single attack which uses surprise and the immense fighting skills and firepower of its Aspect Warriors to annihilate the enemy in one swift blow. To this end, the Swordwind employs numerous Wave Serpents and Falcons to move its units into position, from which the Aspect Warriors then launch a devastating all-out attack, smashing into the enemy and giving them no chance to recover.

This kind of attack has proved particularly devastating against the Swordwind's most favoured type of target - enemy colonies. The Biel-Tan apparently see any colonisation by other races as a threat to the future growth of the Eldar empire. It is their philosophy that it is better to eradicate any usurpers as soon as possible before the enemy becomes well established. To this end, there have been countless conflicts between our military forces and the Biel-Tan craftworld. Often the Explorators of the Adeptus Mechanicus discover and colonise worlds near to Biel-Tan's course, only for the Eldar to launch an attack and wipe out the settlers. Thus we must provide heavy garrisons for newly-settled worlds on the southern rim to protect colonists from these sorties by the Eldar, draining valuable resources for battles elsewhere. If Biel-Tan were to be eradicated this would relieve an incredible pressure on our military forces. However, despite my numerous petitions to this effect, there has neither been the military might nor the political will to do this.

The Swordwind has fallen upon other alien races as well. The Orks in particular are hated by the Biel-Tan, as they can rapidly spread across a newly colonised world [with a prolification which we ourselves find hard to forestall]. The starships of Biel-Tan constantly hunt across the stars to destroy Ork spacecraft before they can find a world to engulf with a tide of green warriors. There have been many accounts through the millennia of the Biel-Tan Eldar arriving to help a beleaguered Imperial garrison fighting against the Orks, only for the Aspect Warriors to turn on their erstwhile allies once the Orks have been destroyed. The leaders of the Swordwind also see it as their duty to protect the Exodite worlds from alien invasion too. As the Eldar of Biel-Tan see it, when the time comes for the Eldar to emerge from the shadows and reclaim what is rightfully theirs, the Exodite worlds will be the first staging points for conquering the worlds of other races that have spread across the galaxy. Many an incautious expeditionary force has made planetfall on a world not knowing that the Exodites inhabit it, only to find themselves swept away by the ferocious attack of the Swordwind.

Inquisitor Czevak - Teachings on the Unholy, Chapter XXX,
The Belligerents of Biel-Tan

Related Links:
Inquisitor Czevak on: Alaitoc | Iyanden | Saim-Hann | Ulthwé
Genesis of the Eldar