The hit sound, at least in the trailer (haven't tested in-game yet), is not very satisfying (it sounds like a blocked spear, which is markedly un-satisfying). Perhaps switching it to the spear hit sound (the fleshy 'shunk') on successful slash would be more juicy? Even some sort of swish sound (spear flying, perhaps?) would be preferable to the clink, I think.

Additionally, the sword is quite detailed in terms of its sprite (lots of distinct colors), which clashes somewhat with the typical Rain World style (not strictly a bad thing, just something I'm noticing). If you see this as a bad thing, the sprite could be replaced with a mostly-solid design, where all of the metal (the blade, crossguard, and pommel) is one solid color (pale grey, white, or black would look nice, could even be room.currentPalette.blackColor), and the handle wrap is another solid color (could be brown, could be a different shade of grey, as long as it's visible). Could even be completely one solid color, though that'd be a bit too plain in my opinion. Definitely more of a personal preference, though, regardless.

Those are my two cents.
I'm excited to try the mod out, it looks quite fun, especially in terms of movement!

@haskipend Yeah, obviously the hit sound sounds pretty bad currently. The only issue I have is that a fleshy sound (like the normal spear-hit sound) doesn't sound right in a few specific situations; however, I could just copy some of the spear code to make the sound follow the same logic.

As for the palette, I'm sure you're right about Rain World's visual style. I might touch up the sword to be higher contrast (and thus less colorfully diverse), because at the moment it doesn't mix well with many Rain World environments (probably due to the style difference you noted).

@TheLazyCowboy1 True, true, I hadn't considered the situations where it wouldn't sound right. Spear logic is probably the best bet.
Another suggestion, RW uses those WaterDrip particles absolutely everywhere for juiciness, you could probably spray out a bunch from the enemy on successful sword hit to add satisfying visual feedback.

@haskipend And then turn them red! Jk, I don't much like blood particles in videogames; but yeah, I'll try to copy some more of the spear's code for sounds and particles to see if it makes a significant difference.
I also want to enable custom sword sounds, so people can turn the sword into a lightsaber or something silly like that.