This level is the final clash, and I made it without taking any damage from enemies.
The level itself is quite small, not very hard till the red door. It can be practiced, after many attempts it becomes a routine. Try to save all invulnerability powerups for the boss fight. I used only one before it.
I didn't pick up the 5 mega missiles it's too risky due to the green platformers roaming in that area.
The boss is hard. Make sure you are always cloaked and invulnerable when fighting. Also try to be near him. I think it can damage himself from mega missile blast nearby if it blast you while you are invulnerable. And in this difficulty level he fires a plenty of them.
Make sure to leave the area before your cloak and invulnerability wears off.
(You can see that the boss fires mega missiles while dying.)
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