Demon King F20 short (solo) guide

Objective:
Defeat the Demon King without getting to 0 hearts.

Useful items:
Any of the Snowshoes:
Snowboots make your movement LESS precise, BUT they give instant acceleration, meaning you can dodge certain projectiles and especially lasers which you normally wouldn't be able to.

Attacks and what to do with them:
Summoning mobs:

When you enter the boss fight, this will be the first thing he does 90% of the time.

The Demon King will spawn two different types of mobs during the fight:
1. Chests

Chests are unlikely to cause big problems during the fight, UNLESS they spawn on top of you. In my experience the spawn animation is too short to dodge, meaning you it's up to RNG to decide if you will lose a life at random:

If there are chests in the way of your possible escape route, make sure to prioritise them over damaging the Demon King himself.

2. Flame dudes

These are the biggest issue. They require two hits, have a range attack and tend to hide inside the Demon Kings body. If possible, 'prefire' them if you can when you see their spawn animation:
This causes it to not even have a chance to move away and pretty much instantly die. If they do happen to be hiding inside the Demon Kings body, be sure to relocate. Dodging both the Demon Kings attacks and theirs at the same time will definitely cost you a life if you wait long enough.

Once you are slightly over half way of the Demon Kings health, he will likely spawn a bunch of these in at once. The best thing to do is to stop with whatever you are doing and take care of them first. One is annoying, six is a problem.

Lasers:

These have a limited range. If the Demon King is exactly in the middle, the outer most laser will roughly reach the rope
This is exactly where you want to be standing. You are guaranteed to not get locked in by two or three lasers, since the position to your left or right depending on which side of the map you are on will always be clear. You can spam Axe Throw until he starts moving forwards or when it's time to dodge. This attack will only trigger if you are inside of the lasers range.

If the Demon King starts getting closer, it's important to get on the outer edge of the range as quickly as possible. The lasers together with the Chest spawn are the only two attacks which are pretty much completely out of you control. Don't stop moving and pray to get to the other side. If you followed the Summoning Mobs tip, your escape route will likely be clear of mobs, since you took care of those beforehand.



Fireballs:

Similar to the fireballs of the Flame mobs, these are a ranged attack. The difference is that they can cross they entire map before despawning.

The hitbox of these are slightly questionable, so be sure to play it safe:


If the Demon King is in this attacking stage, it's probably the best to just Attack > Jump > Attack > Jump and so on.

Final tips:
Time is absolutely no issue. Just play it safe (as said many times before), solo the fight will take ~6-10mins max. RNG is a big factor, so don't be too demotivated if you are failing a lot; my runs probably succeed ~2% of the time if not less.

Also DONT DIE ONCE THE DEMON KING IS DEAD, THE SUMMONED MOBS CAN STILL KICK YOU OUT!!!

Thanks for reading, I hope this is useful in some way.

Also if anyone else has more tips, they are 100% welcome and I can probably use them myself too lol.