Varnish

Red - Nearby players have half as much invulnerability time, This cannot be stacked.
Orange - Fall damage does not affect nearby players, and increases their mining speed.
Yellow - Acts like the sun and burns undead mobs walking on a block coated with this paint.
Green - Creepers walking on the paint get badly damaged, and naturally bonemeals the surrounding area.
Lime -  Extinguishes any fire on top of the paint, including players and mobs.
Cyan - While near the paint, applies the calmed effect. Increasing oxygen, mining speed, and reach.
Light Blue - Freezes nearby water and replaces packed snow with snow blocks.
Blue - Sneaking on a block coated with the paint randomly changes the weather with a cooldown.
Purple - Slowly pulls players toward the paint.
Magenta - Transforms nearby overworld into the nether, with diamonds having a chance to become Ancient Debris.
Pink -  When right clicked with a enchantable item, either adds random enchantments to it, adds a enchantment 1 above the limit, but adds a modded curse, or adds a modded enchantment.
White - Clears the effects of every player nearby, like milk.
Black - Applies Blindness, Darkness, and Shaded when walked on, which all darken the screen.
Gray - When walked on, Applies the Obstructed effect, Majorly slowing down movement, but attacks only do half a heart.
Light Gray - While nearby, adds a dense gray fog.
Brown - Naturally places saplings on nearby grass, and adds regeneration to any player nearby.