"The mechanical core has detected a high-energy life source, please put it in the absorption tank." After the electronic prompt sounded, a cylindrical metal slot rose again on the main center console of the cab.

After Han Feng got into the car, he first glanced at Wang Yingyu, who had fainted in the passenger seat, and found that she was indeed just out of strength, so he breathed a sigh of relief.

In fact, it is a very dangerous thing for an evolutionary to completely overdraw his own energy, but fortunately, Wang Yingyu has just become an evolutionary and has not mastered the way to overdraft his energy.

Han Feng carried the unconscious Wang Yingyu to the sofa in the living area and let her rest, and then walked back to the cab quickly, looking at the cylindrical metal slot in the center console in front of him.

With the experience of the last mechanical core evolution, Han Feng basically didn't think much about it, and put the life core in his hand into the cylindrical metal trough.

With a mechanical click, the cylindrical metal trough slowly retracted after receiving the life core, and at the same time, a hologram of the Unimog RV appeared in Han Feng's mind.

"The mechanical core has successfully absorbed the high-energy life source, and the mechanical core has evolved since its beginning, please choose the direction of evolution."

After hearing the electronic sound again, it was still the same as the last choice, and Han Feng, who had already made a choice in his heart, directly moved his gaze to option six.

"Option 6: Add a vehicle-mounted weapon system, a Sky Dome ultra-high-energy electromagnetic cannon module, and call 200L of fuel to convert into high-energy electromagnetic waves for each shot, causing a wide range of damage, with a cooldown time of 1 hour."

This battle with giant zombies and mutant giant tortoises made Han Feng more aware of the lack of attack methods at this stage, especially in the face of some huge mutant beasts, the disadvantages of the Unimog RV were undoubtedly highlighted.

At this stage, the Unimog RV can effectively defend against the attacks of ordinary zombies and cause damage to ordinary zombies, so that Han Feng and Wang Yingyu can have a relatively safe and comfortable living environment.

However, after Han Feng and Wang Yingyu both became evolutionaries, the function of the Unimog RV seems to be a little insufficient, according to Han Feng's current strength and vision, he can single-handedly take on hundreds of ordinary zombies, and the attack power attached to the RV can only be regarded as better than nothing.

In the face of bronze-level zombies and bronze-level mutant beasts, the shortcomings of the RV's lack of attack power are exposed.

In this battle, Han Feng's main lethality comes from the RPG-7 bazooka, without that bazooka, Han Feng can only watch the mutant giant turtle crash the giant zombie into the Qiantang River, and there is nothing he can do.

So he now urgently needs to improve the Unimog's offensive ability.

After Han Feng clicked on option six, the electronic prompt sounded again: "Selected: Add on-board weapon system, Sky Dome ultra-high-energy electromagnetic cannon module, high-energy life source up to standard, please put fifty kilograms of metal osmium in the pop-up physical material conversion cabinet." (It can be temporarily replaced with 500 kg of ordinary metal, but the replacement barrel is a disposable device, and after one use, you need to continue to put in 500 kg of ordinary metal to make a replacement barrel.) ）”

After the electronic sound prompt, on the unimog RV hologram, a rectangular metal cabinet suddenly protruded from the position of the RV chassis and rose to the front of the car, as if waiting for physical materials.

"it!"

Faced with the sudden prompt of the electronic sound, Han Feng's eyes widened, revealing an incredible expression.

Originally, he also thought about adding a vehicle-mounted weapon system, which only required a high-energy life source, but he did not expect that in addition to the high-energy life source, he would also need fifty kilograms of osmium metal.

Osmium metal is a heavy platinum group metal, and it is also the densest metal known at present, which is extremely hard, and the reduced metal is blue, which is usually doped in bearings and other items that need to be worn for a long time.

"Osmium metal, it's a little difficult!" Although Han Feng has a certain understanding of osmium metal, the price of this thing is very expensive, the price of one gram is cheaper than gold, and the inventory is very small.

Since he couldn't get so much metal osmium at one time, Han Feng could only turn his gaze to the remarks in the back, although it was said that five hundred kilograms of ordinary metal could make a one-time cannon barrel, but in the last days, except for some big cities, it would be a bit troublesome to find five hundred kilograms of ordinary metal at one time in other places, in case it was consumed at that time, and there was no place to replenish it, it would be embarrassing.

However, now Han Feng is still very confident in finding 500 kilograms of ordinary metal, and he believes that there will definitely be a stock of metal in the warehouse of the militia station.

From the hologram of the RV, after learning about the on-board weapon system, Han Feng turned his gaze to option eleven.

"Option 11: Open the equipment manufacturing workshop, and add an equipment workshop to the rear of the vehicle, which can absorb items of most materials, and directly create equipment through the automatic equipment manufacturing instrument."

The Equipment Manufacturing Workshop is the evolution option that Han Feng is most interested in in addition to the current much-needed on-board weapon system.

Judging from the previous battles, the lack of weapons and equipment also limited Han Feng's strength, and he clearly felt this when he was cutting the corpse of the mutant giant turtle just now.

The tactical saber in his hand, although it is forged from carbon steel, has layers of beautiful moire on it, but when this weapon cuts the dead mutant giant tortoise, he can feel a strong sense of sluggishness, like using a saw to slowly sawing the skin and flesh of the mutant giant tortoise, if it is against the living mutant giant tortoise, this tactical saber is estimated to be able to barely cut through the skin of the mutant giant tortoise.

Therefore, the higher Han Feng's evolutionary level, the less this tactical saber will help him, and his evolution ability is still a melee attack type, and a weapon in his hand is extremely important to him.

"Let's try the Gear Fabrication Workshop first." Due to the lack of key materials for the vehicle-mounted weapon system, Han Feng decided to upgrade the equipment manufacturing workshop first, and if the high-energy life source overflowed, then he would choose the vehicle-mounted weapon system next.

Thinking of this, Han Feng made a new choice, clicked on option 11, and opened the equipment manufacturing workshop.

"Selected: Open the equipment manufacturing workshop, the high-energy life source is up to standard, please put 700 kilograms of ordinary metal and 40 kilograms of rubber in the pop-up physical material conversion cabinet"

After listening to the electronic sound emitted by the mechanical core, Han Feng's face twitched again, although the materials needed to open the equipment manufacturing workshop were much more ordinary than those of the vehicle-mounted weapon system, but the quantity required was more than the vehicle-mounted weapon system.

"We can only see if there are so many materials in this warehouse." Han Feng opened his eyes after knowing the materials needed to open the equipment manufacturing workshop, and his gaze immediately swept through the windshield to the gray metal door in front of him.