So, I've made a procedure for activating an aura around the player when they hit a certain key. (R and X to be exact) They do certain things too, but as of now, they only release this buggy custom particle that I made which looks trashy in the long run and I wouldn't want that to be what the aura looks like when I upload the actual release of the mod. I've seen this exact topic before, but in 1.12.2, and when I asked if he'd figured it out, the topic was archived because of support no longer going to 1.12.2, which I don't use anyway, so it's fine.
As said in that post, I too would love the aura to look like this. Also, they gave the link to an outdated resource at https://greyminecraftcoder.blogspot.com/2014/12/the-tessellator-and-worldrenderer-18.html. The author of the topic seemed to understand how to do it and said he'd update if he had any problems understanding. He never posted again, so I'm wondering if he figured it out. The topic that was used in the link was for making a block I believe, but I'm trying to make a particle that looks like that and comes off the player in all directions. Basically, the aura I have only comes out in the player's direction, which I can't seem to fix, and so when I make multiple particles spawn, it doesn't encompass the player like the aura in the picture and just looks like multiple auras side by side. If I could get any help, that would be amazing! I'm terrible at coding, so if there's a slow paced reply, that would be great, and also if you could tell me where to insert the code portion. Thanks again!