DC Universe Online/YMMV


 * Nightmare Fuel: All those Exobytes are from future (read: more experienced) versions of the League and Legion. They have infected thousands of people, enough that there's a hospital full of experimented-on NPCs, and Power Girl giving speeches at the university on how to use your new powers responsibly. And there is nothing saying a single people has one set of Exobytes OR that they stick to their original's alignment. So let's put together a scenario: Kryptonian Exobytes mixed with Joker Exobytes infect an arsonist in prison, producing a superpowered firebug essentially trained by Clark Kent and the Joker. And his powers are still growing...
 * In play, one of the first missions that Lex Luthor puts his prodigies to is to infect university students with a mutagen which turns them into junior versions of the Parasite, with no indication that long term infection can be cured. Per the entry for Deadpan Snarker, Calculator comments that there's no way he can see that going wrong, and that's without considering the welfare of the students (because Calculator, Luthor, and the player villain certainly don't). Bonus! He later combines the Parasite DNA with Doomsday DNA and lets it loose in Smallville KS.
 * One sidequest of the Captain Marvel story arc has you defuse Joker Venom from a break-in a few days back, inside a warehouse filled with zombies. The very last one is in a hidden back room that has more in common with the Joker Missions than the current one. And then you see the Zombie Joker Goons.
 * The way to the room is indicated by a red arrow painted on the floor... and it's very easy to mistake it for something other than paint. It IS just paint, right?
 * In Metropolis, heroic characters are often tasked with saving citizens before they turn into apes, or fish men, or some other suitably Silver Age chicanery. In Gotham, when dealing with the Joker? Victims are strapped to huge blocks of C4 with a timer, where your failure means their death, end of story.
 * Playing in the Arkham Asylum Alert can be quite creepy and the voice that sometimes blends in doesn't help either.
 * And the Fandom Rejoiced: A Flash DLC you say? And it's going to included Lightning characters like Black Lightning and Static?!
 * The Last Laugh (DLC 4) is PVP-based, much to the joy of PVP players who felt neglected. Also implies to have Joker-based quests with Mark Hamill reprising his role as The Joker (After believed to have retired the role after Arkham City).
 * Demonic Spiders: The Joker androids. They have a powerful explosion attack that reduces their health and explode when they die. Even if they died due to the explosion. Both, combined, can take away 90% or more of a hero's HP.
 * The Green Lantern/Sinestro Corps members in Metropolis. They swarm, often have shields you have to break before doing normal damage, and can send you flying backwards (or pull you towards them, so you can't easily escape) with ease. The Green Lantern centric duo is even worse in some parts.
 * Any enemy that can "ground" you.
 * Fridge Brilliance: After the Fridge Horror hit me, this bit of Fridge Brilliance did as well: "Why are the Iconics standing around tutoring cub heroes instead of out there fighting the surge in crime?" Well, their rogues gallery just QUINTUPLED! They don't have the time to fight crime and still have a normal life!
 * And they do get out of the office occasionally, particularly during the "mentor arcs" where you join them to fight their opposite number.
 * All the pre-order copies have different bonus items depending on where you bought them. Three guesses what the item for Amazon.com pre-orders is, and the first two don't count.
 * A lot of the "briefings" and whatnot you can discover throughout the game have snippets from something called "Daily Planet Live", with Lois Lane giving a news report. Why would the Daily Planet be giving a live show? Well, the New York Times and Washington Post got their start as newspapers but have had to diversify in the last decade in order to stay in business with newspaper revenue going ever downward! Of course the Daily Planet would have to branch into other forms of media, too, if it's going to survive in the Internet era!
 * Plus, the Daily Planet is currently Bottled, so it's not like they could really get access to their presses at this point in time.
 * Most Annoying Sound: Fighting Demons in Metropolis. "How Daaare You!" "The Wrath of a hero! Delicious!" "You Will Regret That!"
 * Harley Quinn is easily the worst offender. Her boss fight consists of her making the same terrible hammer puns (about 5 in total) every time she attacks, which is every few seconds.
 * She's just as bad on the Villain's side as a Damsel in Distress, just replace hammer with bird puns. Robin futilely tells her to shut up.
 * Recycled Script: A lot of the arcs are basically rehashings of old DC Comics storylines. Of course, since most of the people who play this game probably aren't familiar with most of these stories, this might not exactly be a bad thing.
 * And let's be honest, those that are familiar with the comics are going to get a kick out of being able to take part in stories like Blackest Night or the Sinestro Corps War.
 * The Exobytes idea is lifted from 52 when Lex Luthor gave everyone powers. When he decided he had enough he turned them off while some were flying etc. Rain of the Supermen indeed. Kinda makes you wonder what would happen if the exobytes are suddenly turned off... Gulp.
 * Another story arc from 52 involves Intergang planning to sacrifice the "daughter of Cain" for their Religion of Crime. You play it in the game, so if you've read the story you'll see the twist coming a mile a way. Still very exciting and loads of fun to play.
 * That One Boss:
 * Bruno fucking Mannheim. Not only are you completely outnumbered, but Bruno has a beam attack that grounds you, is impossible to dodge, and shaves off so much health.
 * Black Adam. Aside from his Word of Power being enough to shave off half of your health, absorbing Zatanna's and (to a greater degree) Giganta's powers is considered him being at his most dangerous.
 * That One Level:
 * The mission to rescue Supergirl from the metahuman hospital has its first encounter with Doctor Psycho early on, but it is a 'game of hide and seek' where you have to blunder around the room until you are close enough to see him only to be able to hit him a few times before he vanishes again. There is no threat to you, but it takes time and you really don't do any damage to him either. And it's one of the challenge modes at 30, later on. It's one of the most difficult ones due to the encounter after that little game of hide-and-seek.
 * Fortress of Solitude 2: Power Core. There is a portion of the mission where your team will have to split into two groups to proceed which includes taking on two Brainwashed and Crazy Kryptonians (one for each group). Good news: You only have to take off around half of their health. Bad news: If the other team goes down before you can cause them to retreat, one of the aforementioned Kryptonians will enrage and curbstomp your team quickly.
 * They Changed It, Now It Sucks: The Flash's voice change has not been viewed favorably by a strong portion of the player base.
 * Now, it's Booster Gold's turn and the reaction's about the same.
 * Villain Decay
 * Veronica Cale, one of Wonder Woman's enemies from her comic, was a cool and calculating scientist and strategist. In the Oolong Island Alert, she is a ranting raving whiner reminiscent of Starscream (not the trope).
 * She's been portrayed in this manner in the comics as well, most notably after she became president of Oolong Island (as seen in Keith Giffen's recent Doom Patrol series).