duck

Vector3 idleWeights = new Vector3(0,1,0);
if (energy > 0.5) {
    idleWeights = Vector3.Lerp( new Vector3(0,0,1), (energy-0.5f)*2 );
} else {
    idleWeights = Vector3.Lerp( new Vector3(1,0,0), energy*2 );
}
animation["lowIdle"].weight = idleWeights.x;
animation["normalIdle"].weight = idleWeights.y;
animation["highIdle"].weight = idleWeights.z;