No math needed at all. It's hard to explain, but you end up understanding orbital mechanics visually and by feel. It's really just a game about speeding up and slowing down.
Is there a space game where there is math required? I'd like to play a game where I'm less of an aerospace engineer, and more of a 1960s astronaut, doing Emergency Slide-Rule Sums™️ during landing.
"Orbiter" might be what you're looking for. It's less "game" and more "sim". There are computerized aids for most things, but you don't have to use them. You might find that rather challenging, though - even 1960s astronauts had electronic computers!
Bonus - it's free. I've burned a lot of hours in Orbiter.
