Use this to update a game's FNA installation!

fnaUpdate.sh

#!/bin/bash
# FNA Update Script
# Written by Ethan "flibitijibibo" Lee
#
# Released under public domain.
# No warranty implied; use at your own risk.
#
# Run this script in the game's executable folder.
#
# This script requires the following programs:
# - git
# - msbuild, which should include a C# compiler
#
# You may want to update MonoKickstart as well!
# https://github.com/flibitijibibo/MonoKickstart/tree/master/precompiled

# Be Smart. Be Safe.
set -e

# Move to script's directory
cd "`dirname "$0"`"

# Grab native libraries
curl -O https://fna.flibitijibibo.com/archive/fnalibs.tar.bz2
tar xvfj fnalibs.tar.bz2 lib64
rm fnalibs.tar.bz2 # Wouldn't want to waste disk space, would we...

# Download and build latest FNA
if [ -d "FNA" ]; then
	cd FNA
	git pull
	git submodule update
else
	git clone --recursive https://github.com/FNA-XNA/FNA
	cd FNA
	curl -o FNA.Settings.props https://flibitijibibo.com/Terraria.Settings.props
fi
msbuild /p:Configuration=Release /p:Platform=x86 FNA.sln
cd ..
cp FNA/bin/Release/* .

# We out.
echo Complete!

Yep, that worked! I was running just by "Run in Konsole" via the context menu. I had also forgotten how to open the script from terminal... Was it an issue of Manjaro using zsh by default instead of bash?
Thanks for the help and quick reply!

Got caught up with something almost immediately after running that script, but finally got to try running Terraria... and it crashes after a couple seconds with a black screen. Any ideas?

@MyNameIsKeegan been getting the same error, seems to this:
Exception: System.TypeLoadException: Could not resolve type with token 01000203 from typeref (expected class 'SDL2.SDL_image' in assembly 'FNA, Version=22.2.0.0, Culture=neutral, PublicKeyToken=null') at (wrapper managed-to-native) System.RuntimeMethodHandle.GetFunctionPointer(intptr) at System.RuntimeMethodHandle.GetFunctionPointer () [0x00000] in <d1664be62cd44600bbd25f7afa292479>:0 at Terraria.Program.ForceJITOnAssembly (System.Reflection.Assembly assembly) [0x00060] in <2587bb223ae24a7fa015a01bdfbc78b9>:0 at Terraria.Program.ForceLoadAssembly (System.Reflection.Assembly assembly, System.Boolean initializeStaticMembers) [0x0000d] in <2587bb223ae24a7fa015a01bdfbc78b9>:0 at Terraria.Program.ForceLoadThread (System.Object threadContext) [0x00005] in <2587bb223ae24a7fa015a01bdfbc78b9>:0 at System.Threading.ThreadHelper.ThreadStart_Context (System.Object state) [0x00025] in <d1664be62cd44600bbd25f7afa292479>:0 at System.Threading.ExecutionContext.RunInternal (System.Threading.ExecutionContext executionContext, System.Threading.ContextCallback callback, System.Object state, System.Boolean preserveSyncCtx) [0x00071] in <d1664be62cd44600bbd25f7afa292479>:0 at System.Threading.ExecutionContext.Run (System.Threading.ExecutionContext executionContext, System.Threading.ContextCallback callback, System.Object state, System.Boolean preserveSyncCtx) [0x00000] in <d1664be62cd44600bbd25f7afa292479>:0 at System.Threading.ExecutionContext.Run (System.Threading.ExecutionContext executionContext, System.Threading.ContextCallback callback, System.Object state) [0x0002b] in <d1664be62cd44600bbd25f7afa292479>:0 at System.Threading.ThreadHelper.ThreadStart (System.Object obj) [0x0000f] in <d1664be62cd44600bbd25f7afa292479>:0

For anyone in the future, I fixed this by downloading FNA myself and changing the Makefile to have
lib/SDL2-CS/src/SDL2_gfx.cs \ lib/SDL2-CS/src/SDL2_image.cs \ lib/SDL2-CS/src/SDL2_mixer.cs \ lib/SDL2-CS/src/SDL2_ttf.cs \
at the bottom of the sources list, game runs significantly better now

It runs now! And of course much better performance, thank you for your help! Audio is a bit crunchy and crackly now which is annoying but a big step forward from black screen.

msbuild can be installed on arch linux with the mono-msbuild package

Msbuild doesn't seem to work for me, so instead I just used xbuild and it worked flawlessly