From a lot of the posts I see around lately, I also get the sense that some people aren't sure what might or might not be at E3, even for already announced games, so hopefully this will provide some clarification.
To note, while you're free to submit things, I'm using my own judgment on what to include, especially for rumors or speculation of what's included in conferences.
Press conference previews (in chronological order):
Officially in the press conference:
- Star Wars Battlefront II
- FIFA 18
- Madden NFL 18 (expect a lot from this due to the new engine and multiple new modes)
- NBA LIVE 18
- Need For Speed: Payback
- Battlefield 1: In the Name of the Tzar
- Two unannounced games
- "Other surprises"
- The Sims Mobile
- The Sims 4
- New content from Star Wars: Galaxy of Heroes
- New content for Titanfall 2
- Madden NFL Mobile
- NBA LIVE Mobile
- EA SPORTS FIFA for Nintendo Switch
- Hazelight's new game has been teased for E3. Hazelight is the development team that was behind Brothers: A Tale of Two Sons back when they were at Starbreeze. We saw a preview of it featuring two men on a train.
- BioWare's new IP was originally slated to unveil at E3. The game has since been delayed for an unknown amount of time, and it is no longer clear if it will be debuted there.
- EA has an "EA Originals" publishing initiative featuring indie games targeting 3-4 release as year. Known titles for this initiative include Unravel 2, Fe, Sea of Solitude, and the above mentioned Hazelight game. It's plausible they will show more than one title from this branch.
- While Visceral's Star Wars game has been in development for quite a while, it's not due to be out until Fall 2018, so don't hold your breath for a new showing unless EA feels they really need more out of their conference.
- While Plants vs. Zombies: Garden Warfare 3, Titanfall 3, Respawn's Star Wars game, the next Battlefield, Dragon Age 4, and Motive's new IP open world game all appear to be in development, none of them seem likely to unveil here, so if you're only here for one of those, it's probably not worth it.
- EA usually has a segment about their esports division at their event. I can't imagine this year will be any different.
- EA will have a 20 vs 20 player Battlefront 2 livestream of the "Assault on Theed" prequel trilogy map featuring your favorite YouTubers, Twitch Streamers, and more. No word on if this will include celebrities on drugs.
- Nas and other musical guests will be present for a concert, though I'm not sure if that's part of the livestream.
Officially announced games:
- This isn't a game, but the Xbox Scorpio will be formally unveiled at E3.
- State of Decay 2
- Sea of Thieves
- Crackdown 3
- Below: Long in development, still not out, but in theory out soon-ish.
- Cuphead: See Below.
- Pit People: Is in early access.
- Full Metal Furies: It's coming to PC and XB1 with no other platforms announced, so I'm assuming it's partnered with Microsoft?
- Forza 7 has been all but announced
- Ori and the Will of the Wisps was trademarked
- The Ashen developers mentioned that their game would be shown again soon.
- There's something "small" related to Halo that is not Halo 6 and not Halo 3 Anniversary
- Microsoft has a marketing partnership with Middle-Earth: Shadow of War. It is always plausible that marketing partnership games show up on stage.
- Studio Gobo signed their partnership with Microsoft a short while ago. It's probably too early for their game unless they had been working on it for a long time, and only just recently announced the partnership.
- It seems too early for Gears of War 5, and Halo 6 is already confirmed as not showing.
- I could really use your help filling this one out. I admit my domain knowledge here is not what it used to be.
Officially announced games:
- None actually.
- Bethesda put out a teaser for "Bethesdaland" that included the following: Doom, Elder Scrolls, Dishonored, Prey, Quake Champions, Fallout, and two "Under Construction" zones. For the sake of discussion, let's assume these are all present at E3.
- Elder Scrolls: Presumably this is The Elder Scrolls Online: Morrowind, The Elder Scrolls Legends (the card game), and/or the Skyrim Switch port.
- Fallout: Bethesda has both Fallout 4 VR and Fallout Shelter they could talk about.
- Quake Champions: This is an unreleased game that still has new modes and presumably more champions to unveil.
- Prey: Um... Well it just released, so they could just show a recap trailer like they've done in the past for recently released games, or maybe announced DLC.
- Dishonored: This would presumably be some kind of (standalone?) DLC?
- Doom: Doom VR is a thing. id said an expansion DLC thingy wasn't off the table, but it didn't really sound like it was definitely coming either, so don't get too excited on that front.
- Unannounced Game 1: Wolfenstein: The New Colossus was teased last year, so presumably it has to be ready to unveil by now. Given the title, presumably it features Anya heavily and follows the same storyline. Anya's voice actor also mentioned she was doing voice recording for the game (which is how it originally leaked).
- So there's a few options here that we should go through.
- The Evil Within 2 is known to be in development via resumes (and seems to have some kind of online mode).
- Bethesda (the publisher)'s job postings also imply they have a MOBA in development.
- Battlecry has been making some kind of online game with narrative for a long time. There's Marvel imagery on their site, though they could also be doing some kind of online for Wolfenstein given some of their older job postings, hard to say. Those might have just been for Doom and the studio was really confused what "unannounced game" meant.
- Bethesda Game Studios (the developer of Fallout/Elder Scrolls) has two new AAA projects (at least one with online) in development that are "a while" off, and a new mobile game that might be closer. [Update: One of these AAA games seems to be a freemium title.]
- ZeniMax Online (TESO) is also making mobile games.
- Escalation is working on VR games.
- It's not impossible that Bethesda (the publisher) is working with an external developer on a project, even if most of their games are internally developed.
PC Gaming Show:
Officially announced games:
- XCOM 2 (presumably an expansion pack)
- Klei (Mark of the Ninja, Don't Starve) will announce a new game at the PC Gaming show.
- They do state there will be new game announcements
- The PC Gaming Show is sponsored by Bohemia Interactive, CyGames, Nexon, TripWire, and Xbox.
- Bohemia Interactive: Arma 3? DayZ?
- CyGames: Shadowverse, though we don't know if they're bringing anything else as well.
- Nexon: LawBreakers?
- TripWire: Probably a mix of Killing Floor, Red Orchestra, and/or Rising Storm
- Xbox: This will presumably just be some of their games from the Microsoft conference, so see that list
- They could definitely do a better job making this sound exciting. Let me know if I missed anything about this.
Officially announced games:
- Assassin's Creed: Origins
- Far Cry 5
- The Crew 2
- South Park: The Fractured But Whole
- A New IP (see discussion below)
- Mario x Rabbids: Kingdom Battle: It's not entirely clear if this will be at Ubisoft's show, Nintendo's show, or both
- The Division: Ubisoft has been saying they plan to unveil The Division's Year 2 content soon
- It's not impossible this is referring to Mario x Rabbids, however, Ubisoft has noted that they have an online centric new IP coming next fiscal year that was originally coming this fiscal year, and Mario x Rabbids is not an especially online centric game.
- Ubisoft has a new space exploration sci-fi game in development code-named Pioneer that was rebooted last year, but was teased in Watch Dogs 2. It wasn't explicitly stated this was online centric, but it would be kind of odd if it wasn't. It could be ready to show by now.
- Ubisoft has surveyed about a new online centric pirate game that would follow up on the core concepts of Assassin's Creed 4.
- Ubisoft has some kind of game being built with Studio GOBO, and I believe both of their new games are online centric based on job postings. This was a third person action adventure title focused on multiplayer combat.
- It's always possible there's something else I missed here. Ubisoft makes a lot of games.
- Ubisoft's online centric Avatar game (by The Division people) will not be at E3 as it is not releasing until at least 2020.
- It's probably too early for The Division 2 or Watch Dogs 3.
- Rainbow Six Siege is not planned to get a sequel until well after Ghost Recon Wildlands gets a sequel, according to their last fiscal call.
- Ubisoft has been rumored to be working on a new Splinter Cell, though it's not entirely clear how development on that is going, as we haven't heard anything in a year or so.
- Ubisoft has said Beyond Good & Evil 2 will not be at E3.
- Aisha Tyler will not be hosting this year, in favor of having developers host.
Officially announced games:
- The below games were explicitly confirmed by Sony in a recent interview.
- Days Gone
- God of War
- Uncharted: The Lost Legacy
- Gran Turismo Sport
- Sony promises "some big announcements" regarding Japanese games. They didn't necessarily say they were exclusive, but they were clear they were console games.
- Detroit: Become Human I had in presumed games before, but Sony didn't list it explicitly when they talked about what they were showing.
- Horizon DLC: Sony has said there's Horizon DLC coming.
- Knack 2: Sony has been known to leave their smaller games out of their E3 press conferences on occasion.
- Everybody's Golf: See Knack 2.
- Matterfall by Housemarque: See Knack 2.
- Dreams: It's still not clear when or if this is releasing.
- Death Stranding: It's plausible Kojima decides to wait until he has gameplay to show now that he's completed a world tour with the game. It's also plausible we'll see something anyway.
- The Last of Us 2: This strikes me as a 2019 title, so it's probably a bit early, but they did announce it super early anyway.
- In theory, Michel Ancel's Wild is still a thing.
- Sony has a new quiz party game called "That's You". You use your phone (and phone camera) in combination with the game. It focuses around doing things with your face and appearance, hence the name.
- Sucker Punch hasn't announced a game in a long time.
- Sony has a VR headset that they might announce games for.
- Sony has a portable system that hasn't 100% officially been killed yet, but don't hold your breath.
- Sony has marketing partnership with Destiny 2, Call of Duty: World War 2, Star Wars: Battlefront 2, Far Cry 5, Marvel vs. Capcom: Infinite, and FIFA Soccer 18, and they usually have one with NBA 2K, so any of those could presumably show up on stage.
- Take-Two has said that Red Dead Redemption 2 won't be at E3, so don't expect that one despite the marketing deal.
- It's always hard to predict what Japanese publishers and developers will do, along with their odds of inclusion in Sony's E3 show, given this has changed dramatically on a year to year basis. The same is true of indie games.
Officially announced games:
- Super Mario Odyssey
- Splatoon 2
- Zelda: Breath of the Wild DLC
- Xenoblade 2
- Fire Emblem Warriors
- Fire Emblem Switch (This is the least likely to be shown)
- Super Smash Bros 4 Switch Port
- Pokemon Stars: This is supposedly an expanded version of Pokemon Sun/Moon.
- I listed Mario x Rabbids: Kingdom Battle in the Ubisoft section, but it's probably worth mentioning here too.
- Monster Hunter Generations Generations Switch Version was announced for the Switch. If it's coming over, this would probably be the right time to announce it.
- Retro has not released a game in a very long time.
- Platinum is making a game for Switch. It's unclear where that is in development.
- Koei Tecmo implied they had a second Switch exclusive. Hyrule Warriors port maybe?
- Square Enix/Silicon Studio's Project Octopath Traveler is quite likely in a showable state.
- I'm not sure if Shin Megami Tensei: New Project is actually very far along in development.
- No More Heroes 3 was announced for the Switch at the system's unveil, but it sounded like it had just started development.
- Miyamoto said that Nintendo was making a new Pikmin game at some point. It's unclear if that's the 3DS game or not.
- Nintendo is hypothetically supporting the 3DS through 2018, so it's not impossible they announce new 3DS games.
- Nintendo will be holding E3 tournaments for Splatoon 2 and ARMS.
- Beyond the above games, there's a wide variety of other third party games that could be shown ranging from AAA ports to multiplatform Japanese games to a huge variety of indie titles. Nintendo is less predictable than most in terms of what they show from third parties, especially when their games aren't at least hypothetically exclusive.
- There was also a rumor about a SNES classic, though it's worth noting that the NES classic was announced on a random day instead of E3.
Notable things about other publishers and developers:
- Devolver Digital will be holding a press conference, but has announced no further details outside of the fact that it wouldn't be held in a parking lot across from E3.
- Square Enix and Deck Nine (Idol Minds) are rumored to be unveiling a prequel to Life Is Strange.
- Crytek's Hunt: The Showdown will be unveiled at E3. It's a "player versus player monster hunter game".
- Twitch has "exclusive reveals" from EA, Deep Silver, 505 Games, and Nicalis. It's unclear if these are new games or new looks at existing games.
- Take-Two (2K/Rockstar) has implied they were not have an especially notable presence at E3. They do have a booth, but probably don't expect new game announcements.
- CD Projekt will not be at E3.
- Sega/Atlus/Vanillaware's 13 Sentinels: Aegis Rim will be at E3.
- Team17's E3 line-up is Aven Colony, The Escapists 2, Genesis Alpha One, and Yoku’s Island Express.
- Focus Home Interactive's E3 line-up is Vampyr, A Plague Tale: Innocence, Call of Cthulhu, Insurgency: Sandstorm, Werewolf: The Apocalypse, GreedFall, and The Surge.
- Roll7 of OlliOlli fame is unveiling their new Unreal Engine 4 based game, Laser League.
- Telltale appears to be making Minecraft: Story Mode Season 2, James Bond: Solstice, and Tales From The Borderlands Season 2 on top of their announced Lionsgate and Game of Thrones Season 2 games. It's unknown if any of these will be at E3, but Minecraft was rated recently, suggesting and unveil soon.
- XSEED's E3 line-up is Zwei: The Ilvard Insurrection, Sakuna: Of Rice and Ruin, Senran Kagura: Peach Beach Splash, and Fate/EXTELLA: The Umbral Star.
- Dragon Ball Fighters by Bandai Namco and Arc System works, a 3v3 2.5D fighting game for PC/XB1/PS4, will be unveiled.
- There's going to be a lot more publisher announcements soon, so this section might get redone, but I wanted to get this thread up early so people could plan vacation time and/or sleeping schedules.
- Feel free to note anything you feel is missing.
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