It had to be done.
Right, so, to get to the point, this is a thread stating what aspects of monsters are broken, imbalanced, buggy, et cetera. This'll go in a list, just naming the monster and what exactly is so imbalanced about them.
Mecha Knights (tier 2, 3)- These guys are fairly well designed, but there's two main things wrong with them. When they block, they can be knocked around from behind, or sometimes with piercing projectiles like Avenger blades. But, when they move, their shield doesn't move with them- that forms a random projectile/player blocking wall where they USED to be. Sense made? Zero.
As for the other thing... Their charged attacks are simply too powerful (EDIT: Tier 3 is meant to be difficult and with little room for error, so this only applies to tier 2). They deal insane amounts of damage, and even with a Vog set, it deals at least half of my health even with a vitapod. Trying to shield will only give you a broken shield. The statuses they dish out additionally are always major, like 12-second Shock. It's predictable, sure, but they run after you much more accurately than normal and at the same speed. When in a group, even when you see it coming, it's basically spelling death, especially considering the previously mentioned bug. Moving on...
Retrodes (tier 2)- Their laser-explosions deal way too much damage, for a mob commonly found in narrow or confined areas, and in large groups. It has high range, they fire quickly, and they deal statuses; why do they have to do so much damage? (EDIT: Doesn't apply to tier 3 because it's meant to be difficult.)
Scuttlebots- Easier than the pre-buffed Jellies. All you have to do is attack them, even with a piercing weapon, and they stop attacking. They move slowly. They deal low damage. They have low range. Fighting them is a pinata party. Give them some other move, something unique, buff their range, make them flinch less or not at all... I don't know.
Gremlin Thwackers (tier 3)- They have no chargeup at all for their spin attack, nothing to telegraph it with, and it deals heavy damage and knockback, sometimes stunning you. Why would you give a monster something so imbalanced, ever? Seriously. At least with Mecha Knights, you see it coming. When they attack twice in a row, they damage you slightly earlier with the second slash than the animation shows. They also have no warning with their throwing attack, except for a split second.
Gremlin Demos- Their bombs can hurt you through walls, and they drop bombs on occasion when hit no matter WHAT it is. Using a weapon like a Shivermist Buster causes them to drop bomb after bomb after bomb, because of the many hits. It really should be based on damage dealt, not the amount of hits...
Gremlin Menders (tier 3)- They can shield instantly, and it heals them. They can knock you back, and in the same process, heal themselves and anything around them. They can attack you with their staff instantly. They can shoot ember bolts at you instantly. They can spawn as many AoE healzones as much as they want wherever they want, healing for a massive sum for how quick they get put up and how often the healing works. They can revive other menders. Hiding behind enemy mobs is fine, but hiding in spikes, or brambles, or status traps... NO. Just no. Why are they so overpowered? Wings are perfectly fine with how much they heal; why is it so different? PLEASE nerf menders, and not buff Wings. (EDIT: While tier 3 is supposed to be difficult, they're completely overpowered compared to Wings, and get so many new, relatively cheap attacks in tier 3)
Devilites- They only flinch due to strong attacks, at the end of combos, or during attacks... and they attack faster than swordsmen are able to counter. And for gunners? They just dodge and move slightly closer with every bullet shot. Cheap. Really doesn't fit in early tiers, maybe it does in tier 3...
Pit Bosses- If they're in the death animation, and they lose their grunts, they magically revive as Devilites anyways.
Greavers- Their status mist hits through walls. Slightly more range than it seems on their melee attacks.
Phantoms- The third hit in their three-hit combo hits much farther ahead than their swords actually are.
Vanaduke- In the third and final phases, lava blocks spawn. And they can spawn ON you. Slag Guards can be avoided by leaving some Skellies alive.
Skellies- In some spots, like corners, you can shove them into them and run away. They turn north and try to move there. Makes avoiding Slag Guards spawning a cakewalk, really. When they leap towards you, there are times where they grab midair and do no damage to you while still immobilizing you, and other times where they immobilize you and use their regular attack twice in quick succession instead. Sometimes when you shove them the instant they 'grab' you, they act like nothing happened and start walking back towards you, even though your character acts like you were grabbed.
Kats- They attack slightly farther with their bite than actually shown. If you're even skimming the bite's special effect, you get hit.
Wolvers (tier 3)- Alphas deal way too much damage. Even with a piercing/normal shield, two hits and it's broken. The animation for a flinching Alpha is very quick an easily overlooked, so you don't really know when they flinch. Alphas and normal Wolvers can teleport instantly while being attacked, and turn while attacking and teleporting. Meaning, they can start attacking, teleport behind you randomly (even without firing any projectiles) and they continue the attack.
Jellies (tier 2, 3)- Their ranged spike attack continues even after they flinch or are defeated.
Lumbers- They can knock you back, but not hurt you, through walls.
EDIT: Rocket Puppies (can't believe i forgot them!)- They deal extremely high damage for how fast they fire, and the missles bounce off harmlessly off of some obstacles. Unlike normal explosions from explosive jellies and blocks, they cause fire for some reason, and despite that, they're in normal arenas instead of fire arenas.
And that concludes this. Any feedback or things to add would be appreciated.
A lot of what you mentioned only applies to tier 3 which was meant to be difficult. Just because you're having trouble doesn't make it imbalanced.