Demonic Spiders / Genshin Impact

• Any enemy with Cryo attacks can be irritating to fight, especially during Timed Missions. Being inflicted with the "Wet" status effect once you've been marked with Cryo (or vice versa) will freeze you solid for a short period. What makes it worse is that Cryo enemies are often found near bodies of water or paired with Hydro enemies, making it easier for them to freeze you. And then there's the issue of fighting them when it's raining...
• In general, Goddamned Bats can become Demonic Spiders in the right (or wrong?) situation or environment. Electro Cicins are Goddamned Bats and are mostly annoyance. But during rain or around bodies of water, the Electro-charged reaction is going to eat through your health, making them legitimately threatening. Or when the area had some burning grass from Pyro slimes, resulting in constant Overload reactions.
• Stonehide Lawachurls, while not considered an "elite" boss, are arguably more intimidating than any of them, due to its strong Geo energy shield and fast-paced attacks. They like to use jump attacks that send shockwaves in all directions. If you manage to avoid getting squashed and aren't in the hard-to-predict line of fire of the shockwaves, its next attack (literally two seconds later) will probably get you... and so will the next attack after that. Abyss Mages each have an exploitable weakness that lets you break their shield quickly, but the Geo-type has none, so it's a slow process, and once it finally breaks, usually after a lot of claymore hits (or one explosive barrel, though there probably won't be one nearby most of the time), you won't have much time before it creates a new shield. Taking them out quickly requires a powerful combo of Elemental Burst attacks, which is hard to pull off without the right combination of characters.
• Hydro Mimics do a lot of damage per attack, each with a specific gimmick: the crabs constantly strafe around you and make difficult targets to hit with precise attacks, the hawks sit far out of melee reach, only coming down to knock you aside with a hard-hitting swoop attack, the boar is tanky and can often run off the battlefield with its charge attack where it can heal back up with little retaliation, the squirrels simply hit hard and have a lot of health while being very agile, the ducks have a constant Hydro damage AoE field around them and move very fast to make it difficult to keep your distance from them, and while the cranes are arguably the least threatening of the Oceanid spawns, as they seldom move and attack slowly, they are often content with simply sitting in the outskirts of the fight and barraging you with ranged wave attacks. The worst one, however, is probably the giant bird, which can best be described as a super slime whose bounce attacks are difficult to avoid and deal more damage than anything else in the fight. To add insult to injury, the giant bird and the frog will explode upon death, which covers a very wide area that is nigh impossible to flee from without getting hurt; the other "reliable" way of avoiding the explosion is to time a plunging attack above the water just right so that the explosion just passes over you while you're submerged underwater, but even that method carries the risk of you drowning if your stamina is low. They're not exclusive to the Oceanid's boss fight, either: you'll have to fight a couple of waves of them in Zhongli's first Story Quest, a prerequisite quest for unlocking Enkanomiya, and in certain floors of the Spiral Abyss.
• Whopperflowers are annoying because if their elemental charge-up is not interrupted, they rapidly fire elemental volleys, leaving the player with a little opportunity to retreat. A worse case happens when you're faced off against multiple of them at the same time, since it's easy to get stun-locked, knocked backed or killed by their ranged attacks coming from multiple directions. They also have the ability to burrow and reappear behind your character, making them annoying to hit.
• Fatui Skirmishers, especially ones other than the Anemo and Geo versions. Their main gimmick is that they can create elemental shields for a short while after initiating combat or losing enough health. Unlike other shields used by other enemies, however, these shields are incredibly resilient to all forms of damage except one particular element they're weak to, meaning if you don't have the "correct" element in your party, you'll be chipping away at them for a disproportionately long time. The only upside is that they'll still take damage to their actual health for as long as the shield is up, but to give an idea of how absurdly durable their shields are, they're more likely to die outright before their shields break without the required element.
• The meteorite challenges during the Unreconciled Stars event turned Hilichurl Shooters into these. They tend to spawn on the very edge of or just outside the ring the challenge takes place, making it difficult for players with ranged DPS to effectively retaliate against them. Hilichurl Shooters during these challenges also always fire volleys of five arrows at a time and are imbued with a specific element, which can lead to you getting Overloaded or Superconducted in the back by a difficult to avoid arrow volley that you can't fight back against.
• Abyss Mages in general hit hard and cannot be injured or interrupted until their barrier is broken, and facing one (or worse, more than one) of them while you are distracted can spell trouble, but Hydro Abyss Mages are most players' least favorite mage flavor. They frequently launch homing bubbles that follow you for several seconds, and immobilize you for several more seconds if they hit you (and they lounge in midair taunting you the whole time). To add to the annoyance, their shield regeneration attack surrounds them with more bubbles, and unless you attack from a distance, you risk running into said bubbles and get stunlocked... again. Before playable Dendro characters were introduced, they also had the toughest shield of all Abyss Mages, requiring a minimum of 12 Cryo elemental application "units" to take down. They're also almost always paired with Cryo enemies, giving them an additional means of stunlocking you. Thankfully, they lose this distinction in Theater Mechanicus, where their slow movement, inability to attack and ready access to the proper elements to shut them down on part of the player turn them into non-threats that can be easily taken care of by a few turrets.
• If an Anemo Samachurl spawns during a Testing Grounds challenge during the "Chalk Prince and the Dragon" event, say goodbye to one of your Ruin Braziers, as it will almost always lead with a tornado attack that will deal obscene damage to the Brazier it targets that will not dissipate when you attack it.
• Blazing Axe Mitachurls are a nightmare in the Theater Mechanicus event. Despite their large size, they're deceptively fast and are much harder to stagger, meaning they're likely to blitz through your Mechanici defenses with barely a scratch (especially if your devices are already pre-occupied with other enemies). Plus, unlike the small speedy enemies, you can't simply knock them over with Anemo characters' wind blasts.
• The Inazuman Kairagis are tough, hit hard, and can be surprisingly quick despite their bulk. They almost always come in pairs, which doubles their threat level, but the kicker is if one of them dies, the other one Turns Red, hitting even harder and healing themselves for 50% health, and becomes immune to being Frozen and Petrified. They can also deflect attacks, so a mistimed Burst would get its damage nullified. All these aspects combined make them absolute nightmares in Timed Missions, particularly the Spiral Abyss.
• The large Rifthounds are a menace to fight. They have many more HP than even Ruin Guards despite looking less durable than them and can inflict Corrosion to your entire party. But the biggest problem with them is their finicky hitboxes and their tendency to flip and teleport all over the place, which makes them incredibly difficult to hit. In the Fontaine quest "There Will Come Soft Rains", you even have the option of calling them your "least favorite monsters".
• Consecrated Beasts are as tanky as large Rifthounds, hit rather hard (including some extremely damaging multi-hit combos), and commence the fight with a significant buff to their damage resistances that can only be removed when they perform a specific attack, which they'll only do 30 seconds into the encounter. Oh, and they all have 50% Freeze resistance, so no perma-freezing them. Fortunately, they're rather rare in the overworld and usually appear singly. However, in the Abyss, they can come in pairs with differing elements, allowing them to easily use elemental reactions against your team.
• Tainted Hydro Phantasms take everything that was annoying about Hydro Mimics and cranks them up to eleven. At first they're manageable, but once they trigger their Super Modes, which they almost assuredly will considering how much health they have, things get bad. Both the melee and ranged forms hit stupidly hard, are completely Immune to Flinching, and gain an immunity to being frozen as well, nullifying the one reliable weakness to the Mimics. Often times the only thing you can really do against them is apply a shield and do what you can to nuke them down, because there's almost nothing you can do to stop their onslaught once they get going.
• Fatui Operatives, like Rifthounds, can also apply Corrosion to your active character and are very agile. However, unlike Rifthounds, their Corrosion is only applied to the active character (instead of the entire party) and is applied alongside Life Bond, which, if healed away, dispels the Corrosion.