I was testing out Bliss shaders with Distant horizons and got it looking amazing, however when i finally got what i wanted.
However, I went into third person and my character is completely bugged.

I'm sorry to say I'm not sure what happened, I didn't notice this bug all the way up until I was preparing to return to my survival world and noticed it last second.
I am not sure what bugged out here or what settings I changed to do this- is this a common issue? Or should I try getting a new version? It looks as if it has a lot of Z-fighting happening, and both images are showing the front view of the character. My first-person arms are not having this issue.
and I do have three mods installed that could change the character, I have Better Combat, 3d skin layers, and shoulder surfing. I'm on 1.20.1 fabric with a bunch of performance mods installed (280 mods including preformance).

I've had a similar issue which i reported a few days ago with light leak fix not working on my character .
I thought to add it here just for the sake of collection

I could replicate this with only :
MC 1.21.1 + Fabric 0.16.3
Iris 1.8.0-beta.3
Sodium 0.6.0-beta.1
DH 2.2.0-a
Using the latest Shader Main file with all default settings except for Old-Light_Leak_Fix set to true
Graphics settings at max except for minecraft render distance at 8 chunks and no Fog culling

Using Nvidia 1070 GPU on windows 10 with Prism Launcher

shoulder surfing conflicts with iris's hybrid deferred rendering for entities

there are 2 ways to work around the issue:

• A: change the shoulder surfing mod config parameter adjust_player_transparency and set it to false
• B: turn off TRANSLUCENT_ENTITIES in shader settings -> debug/experimental

option A will make the camera kinda annoying in tight spaces.
option B will make all entities that were once see-through, completely opaque, and no longer see-through.

as for the light leaking issue, i have yet to look into it. no need to repeat-send it.

Thanks so much! I've been trying to figure that out ever since i set the post! It was the experemental settings, it looks like shoulder surfing didnt have anything to do with it

it is 100% confirmed that shoulder surfing is the cause of the problem, due to how it slightly changes rendering, and how iris responds to the change.