Hi! Gamer Tn here.
I'm going to introduce the way to cheese The Luminous battle.
You can get the Flawless badge, but you can't get the No Weapon badge, because we need to use a weapon.
If you want to beat The Luminous fair and square, I recommend you to stop reading this article and good luck for that fight.

1. Buy MinigunYou can find it in K4L-CUL8-OR'S SHOPPE (the shop near The Luminous on the map).
   It costs 10k gem.
   
   
2. Buy Bullet Grease
   You can find it in Goat Whisper's Store (The shop around the start of the map).
   It costs 1.5k gem (or at least that's what I remember)

Other useful items

• True Aim
• Trigger Happy

1. Kill 1 of the enemies that shoot lasers (sadly I don't know the name of it)
   
   You must kill only 1 of them, and keep 1 living.
   Stand in the middle after you killed 1 of them.
   
   
2. Aim upwards and fire
   
   You don't have to use the 360 aim, just aim upwards and fire.
   
   
3. Jump to avoid getting hit
   
   Just jump. *duh*
   
   
4. Repeat 2 and 3
   Repeat 2 and 3 for 60 times.
   (If you are using True Aim and Trigger Happy too, you only have to do it for 20 times!)

Assert dominance towards The Luminous as it explodes. You can kill the enemy that shoots lasers at that time. EZ. Get that weird thing, and you're done!

(if you mess up the timing to kill the enemy, the (dead) boss starts to explode the platform you are standing on, and you will not be able to win the fight, so be careful!)

That's all!
I hope you have a nice day, and have fun gaming! :)