The Holy Beetle was left by Wang Tao, and its armored form could potentially have a stronger effect in group battles than Wang Tao himself.
Moreover, using the Holy Beetle consumes Crystal Cores, not Wang Tao's physical strength, which is very important. Even though Level 6 Crystal Cores are currently precious, Wang Tao's physical strength is also valuable. Because using any ability drains his physical strength. As long as he doesn't exhaust his physical strength, he can continue hunting zombies and monsters outside. Conversely, if his physical strength is low, he needs to return home quickly.
The appearance of the Holy Beetle effectively increases Wang Tao's endurance. As long as he has enough Crystal Cores, continuous fighting outside for ten days or half a month is not an issue.
