Hello Choo Choo Engineers!
This is a small update. I've added another explosion effect for variety, I've changed the lightning effect to something more dramatic, and I've changed the bullet hit effect to something more substantial.

Also the relic keeper will try to laser your locomotive now, it's still not very dangerous and the laser beam extends out just under 3 meters which means the wrecking ball can still easily hit it. The relic keeper though does retain its melee attack so if you get too close then there will be a bit of trouble on harder difficulty.

I've made the upgradeable cow catcher a little bit more powerful by giving it knock back with the final upgrade. This will allow you to push those zombies aside at higher speeds!

Thanks,
GTGD

Hello Choo Choo Engineers!

Some more additions to the game. I've added a shop track section that appears at about the 70% journey mark.
From the shop you can buy some resources, hire a survivor or a few, and buy another auxiliary system for your locomotive. So you can have up to three auxiliary systems on your locomotive at the same time! I am just a little bit concerned that the game isn't becoming too easy so I'd like to hear your thoughts and experience.
There's a new resource which is money! You get money for every zombie destroyed and it becomes a very large amount by the end of the journey. You can spend some of it at the shop if you want. You can see your banked stats on the main menu and currently these are number of victories, total money and survivors saved.
The new auxiliary system are deadly shurikens that are fired from your locomotive. The ultimate upgrade for it is a devastating saw blade that just keeps on moving and bouncing about the screen by itself. (This auxiliary system is a great pair with the wrecking ball).
Please do let me know how you like the new additions and I do think there is a lack of balance at the moment and I wouldn't mind hearing about your experiences and where I should improve to make the game more engaging, fun, and pleasantly challenging.

Thanks,
GTGD