 The Crash was when Welk and Lomi Plo crashed on a Killik world, in a ship from Myrkr the "Tachyon Flyer" with their prisoner Raynar Thul, a Jedi who was involved in the attack on Myrkr.Raynar managed to use the force to make the Killik heal him but in the process, was made mostly insect and The Joiner King.The Killik share a collective mind which allow them to transmit thought between each other.