I know that this Update is about sound, but I can’t help myself to give feedback on the visuals / graphics that were shown in the videos, particular on the skills Fire Bolt, Fire Ball and Inferno. Sure, their visual designs are not final, but it is important to give feedback early on.
Fire Bolt
Fire Bolt does - from my perspective - not really look like a Fire Bolt, bur rather like a Fire Arrow, as it is very pointy at its tip, instead of having a more rounded shape at the tip, so it feels a bit off, at least for me.
Furthermore, the Fire Bolt travels really fast, which also makes it appear to me more like a (Fire) Arrow Skill being shot, rather than it looking like a Fire Spell.
Maybe that is because that is how I am used to it from having played Diablo 2 for so many years where Fire Bolt has a much more rounded tip and also travels slower, dunno, I just know that these two things make Fire Bolt feel a bit off for me.
Fire Ball
Fireball - as seen in the “Breakable Destructives Sound Design” Video - does imo not look thick enough. The ball feels and looks too sleek for my taste. Maybe you can emphasize the “Ball”-aspect of Fire Ball a bit more and make the ball a bit thicker.
Along with that, the explosion of the Fireball is more like a Nova, rather than an Explosion, which at least for me makes the “explosion” part a lot less visually satisfying. Explosions like these in Diablo 2 and also from other games detonate in a dense, expanding “Fire Ball” / “Fire Orb” instead of a sleek “Fire Nova”.
I hope you are going to make a few more adjustments on that.
Inferno
I know, this is very obvious in an early design phase, but I am gonna give feedback on its visuals as well, since we can’t know what the direction is you wanting to go with it, so I have to give feedback on what you have shown.
It is probably just personal preference, but I would make the whole snake a lot more ethereal and a lot less corporal, if that makes sense.
It currently looks like a physical snake whose body is slightly on fire, which is fine, but imo it could be a lot cooler than what it currently is by making the snake consist not of something physical/dense/tangible, but rather be made of fire itself…
… so instead of a sold body, it could be formed of pure fire itself, which is less tangible/more ethereal than a burning but still physical body.
Maybe you like the image I had in my mind that I tried to convey here as much as I liked it, who knows, but do what you think and feel is right for this skill.
Few examples of beings made of pure fire & flame:
https://www.meme-arsenal.com/memes/5c896da3714b2539f0c093b87c8c28a5.jpg
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To end on a positive note: the Wood Wraiths looks and sounds really cool, I have to admit that.
Maybe in a later Update you also can share more about the music of D4.