Glad you like it! I can explain how it works behind the scenes. It's actually quite simple: 

Each enemy hides itself on Init. There's a Manager actor that checks the score and it Shows the different actors at the correct score. Then they they start their On Update script and that controls their behavior. They have a wait at the beginning of the On Update script to control how long it takes between each attack

I spent some time tweaking how long they wait between each attack so that's probably why it seems like they flow together really well. I made some of them wait for amounts of time that aren't divisible by each other so they don't appear at the same time as others.

As for the gravity settings, that was tricky too. I ended up setting the gravity to a high number (1850) but I changed the Maximum Fall Velocity setting to a low number so the player doesn't fall too fast (3239). The jump velocity is at maximum and I'm using Small Bounce to jum

haha thanks! It’s definitely quirky that the title is on the main screen. I’m glad you liked that and I think Puppers is really cute too :)