My main concern is the game being a Diablo II reboot, mostly in terms of gameplay. Classes/Characters We know of the three classes which are basically 3 from Diablo II (+Lord of Destruction): the Sorceress, the Barbarian and the Druid. They said the Druid doesn't have fire spells anymore which makes sense although fire is an element of nature as well as wind and whatnot. If they decided so, then they should remove any such element manipulation and leave it to the Sorceress. They could make the druid more like Warcraft's with healing, buffs, summons, morphs, damage spells coming from minions and metamorphosis as well as nature manipulation like say interacting with the earth, trees, so on. Rain could be something to consider, storms too but not as much or complex(?) as the Sorceress would handle. When it comes to transformations, instead of rehashing Diablo II, they could be more creative, turn into a treant/ent (thanks @Augustus for the idea), even a raven/roc, flying temporarily from place to place (from highland/cliffs to lowland). Maybe, the instant morph in and out is forced. That should happen with the druid only sketching the transformation as in having some sort of spiritual/astral projection form over the character as a sort of aura and leave actual metamorphoses to abilities and attacks that actually require full attention. The current idea in terms of gameplay might be good but in terms of realism it isn't. Another thing they could do is mix classes. Since druids are related to barbarians, they could make it so that you become a barbarian or a druid depending on what choices you make in the skill/ability & talent/trait trees. The same could be said about the Sorceress and Wizard. Maybe Wizards are more or less destructive or rely on various other elements the Sorceress may not. Similarly with the Demon Hunter and Assassin. Demon Hunters could be the ranged versions and Assassins the melee ones. Monks could fuse with Paladins/Crusaders or something, players would become one of those like with the druid-barbarian and the others mentioned above. Amazons, well, tough, either integrate something like the Rogue or mix it with the Demon Hunter-Assassin class shift. Witch Doctors could be easily melded with Necromancers, each having traits and skills related to their culture. New classes are also welcome. Gameplay Since the game will be an open world and morally gray choice based, what about angelic and demonic affiliation? Basically, players could fight for the bad or good side (or neutral/for themselves?), each of these parties giving various bonuses like more damage against demons or undead and/or enabling using of some special attributes on items, spells/skills, talents, rune words. I'm really hoping they will keep a sort of Diablo III type ability switch option so that we won't need to start multiple characters on the same class to play with the other spells we didn't choose, except if they decide to make class combinations as mentioned above. Drop the cliche and trailer music and put in some experimental orchestral, guitar whatnot music as Diablo has been having. New experimental genres/styles would be welcome. More realism in attacks and movement. Suddenly ceasing a long melee weapon attack and immediately turning around running is too much. Diablo II got it better on this than Diablo but Diablo III turned characters into cartoon superheroes. Since it's an ARPG, they could make stuff like with the Diablo III beta/alpha Siegebreaker Assault Beast biting hero's heads off (last port of video) if they don't quickly react to set themselves free. Story Judging by the gameplay trailer and art we can see Duriel or (a creature like it?) making an appearance. Please don't bring back dead characters. Don't use nostalgia knives and make this more a rehash than an original sequel. No empty and persistent threats from enemies, especially main bad characters. Properly told story through characters/NPC/villains and not by finding long lost kindergarten diaries. Spoiler: Duriel Should be a similar monster, not the actual demon we butchered in Diablo II's Act II ... First picture source: video. The second image is from Blizzard Press Center - Diablo IV - BlizzCon 2019 Press Kit and the image contains the word Duriel Also the concept art from the same link called Duriel... Leoric might be back? Spoiler Hopefully not. We killed the character two times already. It's getting old, repetitive and lame. Source: link. From the intro film (announcement), we can see Rathma (explanation why) and the three people to be sacrificed going to a church which probably is Inarius' Crystal Cathedral. Diablo's manual mentions the cathedral having mirrored glass but I guess that was changed since it also mentions Inarius having a face and eyelids when obviously since Diablo II angels don't even have a face or proper body. We see that Rathma was hiding in sort of a dead man's body (the character also teleported somehow inside through the blocked gate; which brings the question how did the part thing they were going to get out?). Rathma hypnotizes the Zakarum priest into willingly giving blood (so much for mercy I guess; the priest cared about "Rathma") but the other two party members were forced to bleed, thus why did the ritual work? Afterwards we see Lilith basically being reborn and possibly the villain needs time to mature since it looks a bit fleshless (heart being seen through the chest), breastless and covered with blood (and/or as if with amniotic fluid and placenta pieces) as opposed to the concept art. Spoiler: Lilith Sources: video and Blizzard Press Center - Diablo IV - BlizzCon 2019 Press Kit I think the intro needs a bit of work on Rathma's echoed voice. It sounds too, artificial. It doesn't need echoing like that but more of some abyss reverb. We also see glimpses of Inarius being chained somewhere, not in the Cathedral, possibly in Hell as the game external material mentions which retcons Diablo I since the character's Cathedral had mirrors. The angel's wings were supposed to be torn off, I guess only partially now? External material also mentions Lilith being sent to the Void and we see the villain appearing in the/a church, well, actually somewhere under it, appearing out of nowhere going through the blood web. Now, first time Lilith is mentioned in a Diablo game is in the third one, its expansions (Reaper of Souls) if I'm not mistaken. If they decide not to consider too much from comic books, books and other external material, they still have to explain Rathma being their son (if it still is that way) and how the nephalem came to be, the trouble with the Worldstone etc. On Diablo III's end, what will we find out about the powerful nephalem? Will the character be overwritten by Rathma as the killer of both Diablo and or at least Malthael? Or will it be Mendeln/Kalan or Mehtan (Deadly Roots: The Lore of the Necromancer) or just totally unrelated, maybe the Diablo III nephalem hero standing with the remaining Horadrim and Tyrael? They could actually make an interesting conflict between Inarius and Lilith especially in what the nephalem are concerned. Also, let's not forget the Worldstone was destroyed by Tyrael and that the Reaper of Souls hero is a very powerful nephalem. Maybe, there will be a way to choose a Inarius' or Lilith's side or maybe that would only concern the Diablo III nephalem hero since Lilith is supposed to be Diablo IV's main villain/boss. Who knows, maybe the nephalem will gather all humans against both Lilith, Inarius and whatever is left of the Angiris Council and Hell. Other story posts on other threads: Spoiler Blizzcon 2019 Opening Ceremony Blizzcon 2019 Opening Ceremony Blizzcon 2019 Opening Ceremony Blizzcon 2019 Opening Ceremony Blizzcon 2019 Opening Ceremony Blizzcon 2019 Opening Ceremony More suggestions: @Augustus' post. @MasterBlaster's post. @Kerael's post.