That One Sidequest / Xenoblade Chronicles X

• Generally, any mission that encourages infiltration (such as "The Little Rich Girl", "Spy Games", "Prone Sweet Prone", and "Definian Downfall") will become this. In all of these, one must go into no-man's land that are the Ganglion bases scattered throughout Mira. Said bases are crawling with level 40+ enemies, and those are the lower level examples. When fighting more level-appropriate enemies in said missions, damage control is essential.
• An early-game example is "My Dream", Murderess' recruitment mission. Firstly, the game tricks you into thinking it's going to be an Irina mission, and you can only bring one other person besides you and her, because your final party slot is reserved for Murderess... who predictably betrays you. That's not the hard part. She brought backup. Make the wrong choice, and it's necessary to fight two BLADES and a Skell, and the mission is accessible long before you're likely to have one of your own. What's worse is that, even after Murderess leaves, your party is still locked to 3 members, including Irina, who's likely to be woefully underleveled for this fight unless you've gone out of your way to grind her. And this is an affinity mission, so once you start it you're locked in until it's done.
• The affinity quest "BFFs" is not a difficult quest in the slightest bit, so why is it here? Well, this mission is home of a Game-Breaking Bug, and one that is very easily caused nonetheless. Basically, this bug happens when you get the signature from the Dorian Caravan before the Dodonga Caravan. Oh, and by the way, since this is an affinity mission, if you saved after the glitch was activated, it would be outright impossible for you to progress further into the story, so your only option is to restart the entire game.
• "Blitzkrieg" will test your patience, no matter which path you choose. Go with Frye, and you'll have to eliminate enemies entrenched in a fortified Ganglion Stronghold full of level 45+ enemies (the targets are level 30). Said targets are adjacent to a very tough mechanical enemy, making it hard to just target the lesser enemies required. Thought you could cheat the system by going with Phog? Wrong, you'd have to infiltrate said base anyway.
• "Trade Agreement" requires you to perform a Chain of Deals to obtain a Golden Nopopotamus card. To get it, you have to talk to every citizen in New LA with the hope that this one person will be part of the quest... and inevitably, they'll be higher up in the chain. None of this is marked on your map or FrontierNav, none of it is logged, and there's nothing differentiating quest NPCs from normal NPCs aside from their dialogue not having choices. Some quest NPCs are aboard the Ma-non ship. And sometimes, the NPC will require you to obtain a random drop item before they'll give up their card. Worst of all? The quest has branching one-way paths that you won't realize until you find out you traded away an item another person wanted, and nothing changes to acknowledge that. This quest is one that will take ten minutes with a guide or several painful hours without.
• "Definian Downfall" is widely regarded as one of the most punishing missions as it forces you to trek into the Ganglion Antropolis. That alone makes it bad, but to add insult to injury, you're supposed to hunt down level 30+ enemies in a dungeon where most enemies are high 50-low 60, in an area that you must reach by going straight through said high level mobs. That would be hard on its own, but you also have to collect three keys to open a forcefield, the task of which is not marked on the map or objectives, and acquiring one of them requires killing a level 55 Milsaadi in range of a level 84 Seidr Tyrant. And to top it all off, to finish the quest you have to fight none other than the Rexoskell. Twice. It is stronger in the second fight, but it's ironically easier since it takes place outside the Antropolis, meaning that you can use your Skells against it—but the player still has to do the first round on foot. If that wasn't enough, beating this quest is the prerequisite to start several other quests. Get ready to cry bloody tears.
• Getting Mia requires you to go through a ton of hoops before finally being able to recruit her. You need meet her at various points in each continent after clearing certain story chapters, and each time in out-of-the-way areas with no clue whatsoever that anything is there.^note Fortunately, you'll start getting cutscenes of Mia after a point to let you know she's nearby. Every time, you need to do a mission where you help Mia out of a jam on her various misadventures, and every time, you have to clamp down on your better judgement and let her run off into an even more dangerous continent. You also need to finish no less than three quest lines, including the one that ends with Definian Downfall. Then you have to achieve a survey progress of 65% of Cauldros. And THEN you have to go into the Ganglion Antropolis again for the last mission to finally recruit her. Note that Mia's entire recruitment process begins as early as Chapter 4, and can finally conclude after Chapter 11, which is the penultimate chapter in the game.
• "Rise of the Blood Lobster" requires you to find 99 booby-trapped toy lobsters to avert a terrorist attack. They are hidden all over New LA in the most obtuse and hard-to-find of places, including on top of construction vehicles, in the areas below the city, and inside some buildings. While you do get a hint with a red icon that shows up at a certain distance, it vanishes when you get close, and if you get in a Skell, the lobsters become almost impossible to see. Last Lousy Point doesn't even begin to describe it. And it's also made worse by the fact that the quest is divided into two segments where after obtaining about half of the lobsters, another one will show up, most likely in a place you've already checked, which will unlock the other half of the lobsters. This means you literally have to scour all of NLA, TWICE AT MINIMUM! And then have to find a couple of more lobsters that only spawn after getting 97 of them, again in places you've most likely have checked and have no reason to go back to. Also for the record, you can get this quest relatively early on, about chapter 3 or so, and you won't be finishing this until near the end of the game. For some this is easily one of the most frustrating, eyebrow raising, and just down right exhausting quests in the game. And to even be able to get the last lobsters to appear, you have to finish the difficult Definian Downfall sidequest. And while the boss fight at the end of this quest is nowhere near as frustrating as Rexoskell, the fight against Blood Despair/Justin is no walk in the park either. "This Is Gonna Suck" doesn't even begin to describe the feelings of any player even halfway-informed about what they're getting into.
• Any quest that requires gathering rare collectibles can turn into this, such as Hazmat Hunt, asking the player to search for Auroran Bones in caves. Unlike Xenoblade, there's no way to trade for collectibles, so be prepared to walk or drive or fly around a certain area a lot.
• Material gathering, as it can be a Guide Dang It! scenario when it comes to destroying certain appendages to get a higher chance of obtaining materials (and material drops are much more RNG-based than in Xenoblade). That's one benefit that Reclaimer members can yield, as they have a slightly higher chance of obtaining materials.
• Among the Squad Missions, Contamination Nation is the most difficult in relation to its designated level. Skells are prohibited against the giant Purgovents, which take a long time to defeat even with a Skell. There's not much landmass either, limiting the locations to fight. Being above the maximum level is the minimum requirements to get through this mission safely!
• Unnatural Disaster is one of, if not the most difficult of all Squad Missions. You're on Mount M'gando during brimstone rain, and unless you brought a Brimstone Rain Screen augment or you run to the very out-of-the-way weather changer, you'll be taking constant damage and having your attacks weakened. Your enemies consist of three scintimures and a colubrim, all near level 60. All four are giant enemies that possess devastating electric attacks and enormous HP. The kicker? Skells are prohibited. You're fighting four powerful enemies that you'd normally fight in a Skell, on foot, in weather that damages and debuffs you. Unless you bulk up on electric resistance or pick the scintimures off separately (only the colubrim is required to be defeated), you will die very quickly.
• Close Comrades can be difficult for first-time players if they try to take it on at the wrong time, as Selenic Cetos prowl the Qing Long Glade during the night. They are giant enemies 40 levels higher than the enemies you're up against, and since you are required to have Lin and Doug in the party, both of which have AoE arts, it is easy to suffer a Total Party Kill when they accidentally aggro the overpowered flying whales. Aside from that, it's possible for the nighttime energy mist weather to give your enemies a major buff. These enemies (ten germivores and a cinicula) aren't pushovers at this level, either. This mission is also required to start Chapter 7.

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