I am a decently advanced Tier 3 player with a mix of 4* and 5* gear. Whenever I go into a Tier 3 Wolver Den post-patch, I can easily clear the area without having too many issues with even the Alpha Wolvers. I can usually handle Candlestick Keep areas if I stay clear of the Grimalkins and don't get munched on too much. I can usually handle Tier 3 Deconstruction Zones with wise use of my Shadow Driver. Even Shock and Fire areas do not pose too much of a challenge to me, though I've not yet attempted a FSC run and have been putting it off for a long time. All of this solo.
Fiends, however, I cannot handle whatsoever, with the sole exception of Trojans.
I have a Fallen set that I use for Shadow resistance, and try to make good use of a Mega Magnus for killing Devilites and Greavers. It barely helps because I cannot shield their attacks - Devilites are unpredictable and their projectiles move faster than lag lets me respond, meaning as soon as they've thrown the projectile I get hit. Greavers would be tolerable but they seem to stagger their attacks better in groups now and I cannot respond in time with my Flourish-line weapon to hit on all sides of me, especially when they sneak up behind me.
I recently went into a random Clockworks level today and was put in a Tier 3 Shock area. I went into a miniboss room and easily cleared out the Kats beforehand, and then was assaulted by a mob of about 5 Greavers, a Lumber, and a Mender. The Greavers managed to hit me and then I was shock-locked, and had to burn through most of my Mist and two health potions to revive twice before giving up after being killed by stray floppy discs later on.
Not only do I feel that Devilites and Greavers are frustrating and not fun to fight against (my main argument here and the one I feel is the best reason to nerf them), I also feel that they outclass nearly every mob in the game, far and away eclipsing Mecha Knights, Kats, Alpha Wolvers, Trojans, Giant Lichen Colonies, Retrodes, Gremlins, Polyps, and every other tough mob you could name for the title of hardest in the game.
All of the other mobs, while powerful, are fun to fight against (maybe not Mecha Knights due to their broken hiboxes, however), but Devilites and Greavers take control away from the hands of the player and lead to a detrimental experience for all, mostly because their attacks are too fast to react against, too damaging for their speed, and too hard to effectively counter.
I'm not alone here, and I know this is a fairly common suggestion so that what I'm saying is nothing groundbreaking - whenever I go into a party and we are approaching a Devilish Drudgery area, there's an immediate cacophony of complaints and even the forums erupt in anger whenever the pre-Vanaduke stratum turns into a Fiend area, albeit filled with bitter counter-arguments. I'm not alone with my friends on this one - even though Devilites are not as powerful as Alphas or Retrodes or Giant Lichen Colonies, they're by far the hardest mobs to dodge and whenever a party I'm in goes into a Devilish Drudgery area, we're almost guaranteed to wipe once.
(Amusingly, Fiends were apparently designed to be fairly weak: the sign in the Devilish Drudgery area says that Devilites are weak on their own, but become powerful when accompanied by a Pit Boss. Unfortunately, it's a matter of degree.)
tl;dr: Fiends barring Trojans are more powerful than almost any other mob in the game, they're incredibly unfun to fight against due to their ridiculous speeds and the lag ingame, and need nerfing so that they are on line with every other monster family there is. Player skill isn't a good argument when these obstructive bureaucrats can destroy anyone but the 'top' playerbase, and even they have issues.
Challenge. if the game was completly nerfed, people, including you, would be ranting for the game to be harder.
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