Witheria

This mod adds Witheria, a humanoid mech wither. To summon her, go to the nether roof, then summon and kill a wither there. Four seconds after the wither's death, Witheria will be summoned and the battle begins. Good luck!

All attack patterns have unique animations so you know what is coming next. Warning messages will be sent to the chat before every attack as well.

If you learn how to dodge each attacks, it is possible to kill Witheria with no damage taken. All you need is a bow, idealy Power V but not necessary, a stack of block and arrow. No armor nor food needed. I strongly reccomend practicing with cheats on at first, since the boss fight is pretty skill-demanding. I also reccomend building a bunker before the fight begins. Witheria will not break blocks, so the building blocks won't matter. She drops "Slasher", a high spec multi-tool. 

As far as I know, Witheria is one of the most difficult bosses in all Minecraft MODs. It is beatable in vanilla, but that does not mean it is easy with MOD weapons.

I believe some of my procedures help solve problems people have. This mod has following systems:

・Detect if a mob is looking at a specific mob (whether there are blocks between them)

・Laser attack that looks good(personally) and able to track a target

・Headshot detection

・Fully procedually designed flying AI (No default minecraft AI)

・Mob's range attacks that accuracy can be edited

・Rangefinder

・Anti-cheat (Despawn resistance, sethealth resistance, Teleport resistance and so on)

・Procedurally designed knockback