Saccharomyces/Camellia Sinensis Leaf/Cladosiphon Okamuranus/Rice Ferment Filtrate

Also-called-like-this: Hadasei 3TM
What-it-does: moisturizer/humectant

This super-long named thing is trade named Hadasei- 3 and it's Tatcha's "superfluid of Japan’s three essential nutrients of Green Tea, Rice, and Algae ".  The liquid is obtained by fermentation and the basic idea behind any fermented ingredient is that the fermentation process helps to break down the complex bio-molecules in the plants and helps to isolate the beneficial components for the skin. 

The Algae component is claimed to help skin hydration, while rice gives high-protein nourishment and green tea is indeed an excellent anti-oxidant and anti-inflammatory ingredient.