This Seeking Tech guide will show you an easy way to beat Retro Rampage 5 in Astro Bot.
To make this stage easier, you should learn how to use your spin attacks with the Frog Punch powerup. In order to pull this off, hold Square and then let go to perform a spin attack. You then need to hold L2 and R2 down to extend your reach.
Use this attack to quickly take out a bunch of enemies in the beginning, which should make the rest of the fights a lot easier. Use the same attack to take them out.