Artuneon is a single-player space shooter game where you can collect elements by destroying the asteroids in different galaxies, exchange the elements to artunium, buy new ships and be the king of the galaxy by defeating the arch-enemy, Nemesis.

https://theartun.itch.io/artuneon

You can check this playlist for tutorials & gameplay: 

https://www.youtube.com/playlist?list=UU_RUkAMH35yRUuu8Vzjx70A