When the taniwha attacked, it wasn't doing a single minded assault. It didn't only aim at one individual, nor did it show a particular preference to fighting those at close or long range. It certainly was more powerful at close range and its attacks were better suited to it, but that hardly discouraged the beast.
At long range, it continued to attack with its antennae in the same manner that Valheed was slaughtered just moments earlier. Unlike before, the attacks didn't come all at once in a collection but rather they struck at irregular intervals, switching between targets in a terrifying but almost mesmerising display.
As they continuously extended and retracted at odd rhythms, these strange and terrifying eyestalks almost looked like the clawing of a giant thousand legged spider. Of course these limbs weren't the only things active.