Corruption
Based on the Dissolve shader, this shader changes the sprite to have a purple tint.
It needs a Noise texture for the effect, akin to the Dissolve shader
Shader code
shader_type canvas_item;
uniform sampler2D dissolve_texture : hint_albedo;
void fragment(){
vec4 main_texture = texture(TEXTURE, UV);
float dissolve_value = mix(0.5, 0.6, sin(TIME));
vec4 noise_texture = texture(dissolve_texture, UV+vec2(10.0*sin(TIME/5.0),10.0*cos(TIME/5.0))/5.0);
float mult = floor(dissolve_value + min(1, noise_texture.x));
main_texture.g *= mult;
main_texture.r -= mult - 0.1;
main_texture.g -= mult - 0.1;
main_texture.b -= mult - 0.1;
COLOR = main_texture;
}