I've been thinking a bit about the bosses that still miss (fiend and gremlin), and I figured out something. now, I'm not a programmer so I don't know what of this can be implemented/ created, but this is the suggestion section. also, I know of the "major" update, battle sprites, so I expect nothing coming out of this in the near future.
I stop you now from saying: we have a fiend and a gremiln boss! yes, in danger missions and crimson hammer, which are side missions. I count only the bosses in the arcade. thank you for understanding this.

Fiend:
Location: something that recollects a skyscraper, but upside down. so, fiend well? I can't tell any others.
in the levels, there should be a loudspeaker that shouts "overtime!" during battles. this would turn all devilities into overtime devilities at first, but if there is only pit bosses and yesmen on the battlefield, this will turn pit bosses into overtime bosses. yesmen still heal them.
depths: I think of this as a T1 boss, so 3 depths.
depth names: 1 devilite welcome (a lobby) 2 overtime work (offices) 3 boss office (box office? boss room? maybe both)
boss:boss:
the appearance should be more on a normal devilite. just because he dodges bullets like them.
movements should be fixed as the snarbolax if it is a t1 boss; though, I wrote the upper sentence for a reason.
it should have 2 phases.
1 throws boxes, that deal shadow damage. if you come close, he has a melee attack. a 2 hit combo, to be precise. he eventually shouts: "overtime!", which summons 4 overtime devilites.
2 he engrages. he now has a sword for melee. he throws computers at you, which act like bombs (but this is matter of discussion. I really think it's too much for a t1 boss.). he eventually shouts "OVERTIME!", which summons 2 overtime pit bosses and 2 overtime devities.
possible token: devilite curriculum..

Gremlin:
Location: a gremlin city. so, emberlight, but much larger.
depths: I think of this as a T3 boss, so 5 depths. and since gremlins have elemental attacks, I suggest that depths should have their own element. maybe a little randomizer, but I ask too much. this should be a boss stratum.
depth names: 1 blast entrance (fire) 2 envenomed streets (poison) (is that even a word?) 3 schocking resistance (shock) 4 freezing citadel (ice) 5 war room.
boss: maybe a member of crimson order, or maybe just an elite. he has a prototype high-tech armor, which makes him eventually change its attack element.
I'm not so creative to have good phases, but I thought of these. attacks are below.
1 the elemental armor is off. 5 knockers are spawned with him.
2 the elemental armor is now active, but only with ice-poison statuses. 2 twakers are spawned.
3 the elemental armor now is fully activated. 4 twackers are spawned.
4 the elemental armor is now overcharged. this makes him faster, and (if you re so fool to do that) elemental attacks heal him. he changes element on every attack. attacks deal pure elemental damage. a schorcher, 3 twackers and 4 knockers are spawned.
5 the elemental armor reaches its limit. the boss is faster, and every attack has a very high chance to deal a status effect. he randomly explodes, damaging everything in its range. 2 scorchers, 2 menders, 4 twachers and 4 knockers are spawned. (maybe it's a bit too much.)

the armor provides some additional weaponry on various phases. note: they stack.
1 two blades attached on the arms. it has a 3 hit combo that should be: cross slash- cross slash- double stab. only the stab has knockback. each attack can make him move 1-2 blocks forward. the attack is not charged.
2 add two minor guns. they shoot normal bullets, dealing elemental damage accordingly to what is the armor set on. same melee attacks as before, but the stab has now an elemental explosion, like the brandish series.
3 melee attack is now a 5 hit combo. practically, add two double slashes before the 3 hit combo before. add two lasers cannons. they do not deal the same damage of the twins, but they have great knockback. they cannot deal status effects, but they deal pure elemental damage.
4 add two more minor guns (inclined 30-45 degrees compared to the ones before). the guns now attack twice. a charge melee attack is added: he can rotate a blade, put on two rockets and spin for 5-10-15 secs. each normal melee attack now provides a 3 blocks thrust; though, he can now stay still or do the trust on all of his attacks. now there are 3 explosions on the stab.
5 add a bomb thrower. it throws an elemental bomb causing the according status effect. the melee attack now thrusts 4 blocks. the spin attack now ends with a sword slash on the nearest player. the lasers lasts more. the minor guns shoot 4 times.

and now, let the feast of over 9000 complaints begin!