We could say that vampires don’t have a material body and they just alter the wavelength of light that passes through them to project a living form towards the eyes of living observers. That way they could be visible without having a reflection.

Then they could give themselves a shadow by shifting the visible light from bright light sources into infrared or ultraviolet instead of blocking it as material objects do.

I tried Minetest a while ago and was never really able to get into it. The new player experience was rough, a lot of decision paralysis. The texture style can vary between mods and servers. It didn’t feel very cohesive. I don’t know if that has changed since I last played, but to me it didn’t feel like a minecraft killer then.

From what I can tell, Hytale was supposed to be a bit like Terreria in 3D, as well as a platform for minigames. The gameplay and graphics from the trailers looked really good. I’m sure it would have been a Minecraft killer for some. (Ex. players who primarily play for the minigames like bedwars)