Bosses are boring and straight forward, not to mention really easy regardless what difficulty setting it is.
I suggest some mechanics to bosses, inspired by Final fantasy 14, WoW, and Tera (these are the only games I know with some good mechanics)
Black Keep: The silent legion boss is silent but deathly slow, there needs to be a rage mechanic at a certain percentage or random interval after losing health where it speeds up and attacks more often.
All bosses should have some sort of dialogue as well. And a closing to the entrance/exit upon entering and aggroing the boss so that no one can escape until they die or kill the boss, all players who die should have their inventory be spawned outside the entrance of the boss room.
At 75% Health the boss should summon 4 ethereal blades that will strike all sides of the room and Grant the boss an ethereal aura that makes him impervious to all damage, to nullify this, players must destroy every sword within a certain time. As time passes the aura will slowly glow red, the longer, the darker, and if players fail to destroy the swords in time the boss will have a dialogue and move the aura into it’s sword and rotate slash in a 360 which will damage and instant kill everyone in the room automatically. In the event that players do destroy the swords in time the aura will implode on the boss and make him kneel for a few seconds before getting back up again to fight indicating players survived the mechanic.
Dialogue: “Wretched fools, my swords grant me strength of which you couldn’t comprehend”
(Summoning the four swords)
(Failure to complete the mechanic)
At 50% health the boss should jump in the air and float there while throwing it’s sword into certain areas of the room that will cause a torrent of magical slashing waves in all directions that reach a certain distance, once the attack is finished it vanishes in a glow and reappears in the bosses hand to do it again, should be done at least five times before the mechanic ends and drops back to the ground.
Dialogue: “Feel the wrath of the undead!”
(Jumps into the air and floats)
At 25 percent the boss should create glowing magical orbs in the air that will burst in time and damage players, this can be avoided by using a bow to destroy the orbs before they explode.
Dialogue: “Beware exiles, the magic that strikes the soul!”
(Preparing the orbs animation)
I feel like this all would make the fights much more longer and exciting and something to look forward to, especially needing an actual group to fight the boss which should scale with the server settings to balance it out. I’d prefer the possibility of being wiped and having a hard time trying to get the best gear in the game than to have a mundane experience and get it easily.