Yes, it is as VN said.

There are so many factors that add to the difficulty of the game.
Shot range, damage, armor, shot frequency, spawn frequency and count, and more.
The enemies automatically level up after each wave and world.

Until recently, I could very easily play through to the end. Without taking any major losses. Almost boring.
Then I thought to myself, let's just set the armor of the enemies a little higher.
At the same time I added my last ship type. after that the game was no longer manageable.

Still need to tweak a bit.

I know the feeling!
In "Infection" each virus (enemy) style has adjustable speed and adjustable immunity to each of the four styles of defence. The towers also have adjustable fire rates. (adjustable at coding time not by the player).
Tweaking everything to a challenging but not too difficult level of play is the hardest part of creating a fun game.
It is therefore one of the main things that I will be looking for when judging #JustSaying

Ok, I am done now.
Project uploaded to itch.

I wish you a lot of fun with it.
Now I can finally test the other contributions

PS:
With the game difficulty, I don't know if it's that good.
I have played through the game so many times and for me it is easy.
But when I saw my son when he tested it.
it didn't look so easy anymore.
All I can say is that you need the right strategy.

Very nice

I played it.

Good job.

after a couple of runs, i'm figuring out the "strategy" so, maybe a learning curve, but i don't think it will be that long.

meanwhile, at least on my 55" TV, the text labels are tiny. i'll play on my desktop but i'll probably have to screenshot and zoom to read it.

regardless, i'll figure something out. it's prolly the display setting when piping to the TV.

otherwise, good stuff, madbit. congrats on getting it finished and i look forward to giving it a solid go

Thanks all.
I've updated on itch my project.
There is a bug fix for the highscoretable.
And better readable labels. (i hope so)

So, I have now also made a last update to itch.
It fixes another bug with the high score table and a bug with the missile hits.
I also reworked the title screen.

Edit:
I forgot to mention. When you get to the fifth colony and from the fifth wave onwards you have to destroy the enemy mother ship to win the game.