The first type: pea shooter
The zombies in the first stage are relatively simple, basically a pea is an ordinary zombie, and the roadblock zombie needs to be knocked down twice. Tip: Move as much as possible, because sometimes the second bullet is still on the half of the first fallen zombie.
The second type: double shooter
There is no difference between the second stage and the first stage, except that zombies don't become roadblock zombies. Control your double shooter well. Each row needs the stay time of double shooter, so it is no problem to pass the customs easily.
The third type: boomerang shooter
In the third stage, I turned into a boomerang shooter. It is more difficult at this stage that there will be a jet zombie, and I will not be able to kill it for a while, and the speed is relatively fast. Try to kill it with big moves. (You can move up and down by releasing the big move)
The fourth type: triple shooter
We have also become the ultimate form-triple shooter. Zombies at this stage are mecha rugby zombies, and they have no other special skills except extremely thick blood, so they can be easily defeated by keeping the output as much as possible.