I am starting on a project of a planet that is based a round islands in Lava. I could use the mustafar lavadomes, but the look sloppy. In theory, could I use a texture of water that looks like lava, and then put a death region in it? And if anyone has lava water textures, that would be awesome. Thanks!

You can take the .tga file from different water types from the assets and edit them with GIMP or Photoshop or such programs to get what you want.