These files can be resized with less loss via code or directly in an editor.
I recommend Photoshop as that's what I use, but whatever you are skilled with will work just fine.

They are offered as 512 x 512 pixels at 300 DPI which, while increasing detail, tends to increase file size. They can safely be resized to 256 x 256, and even 128 x 128 without much loss. Anything less will become quite pixelated and is subject to your own judgement/preference.

You can also find two files with ALPHA in the name, this is for code color-changing purposes. The alpha back goes behind the alpha front, and you use a fill color code to change the white orb in the background. I included this for those who wish to possibly randomize, or associate more color with less asset space. Be sure to put the back directly behind the front so it all lines up!

Also included is a black background frame with no color or swirl, as well as the original PSD file for Photoshop. Feel free to play around with it.

*PLEASE NOTE*
The weapons shown in this package are available here;
https://opengameart.org/content/bbs-simple-weapons-pack