Varuna

Varuna is the essence of Water and Mind. It is one of the four primary essences known as the Tesseri. In Arcanimancy, it is also known as "Logos".

Core: thought, mental, astral
Aspects: mind, clarity, wisdom, knowledge, logic, memory
Time of day: Twilight
Season: Spring
Colors: Blue, aqua, silver, turquoise
Tools: Sea shells, ocean water, seaweed, cup, cauldron
Crystals: Amethyst, aquamarine, blue topaz, lapis lazuli, pearl

As the essence of the Mind, Varuna is what allows thinking creatures to have rational thoughts, ideas, plans, logic, and memories. Mind touches even non-sapient creatures, like animals, albeit in a more limited capacity. Arcane and occult casters usually excel at mind spells.