What I have so far is that, rather than using only
some types of each
these and
these, it has
all types of them, as well as all 6 of
these.
They are sapient, despite being unicellular (rather than a brain, they have multiple nuclei each; the nuclei double as neuron-equivalents). They can photosynthesize, but they eat stuff too. Although they are unicellular, they're big: about 8 feet in diameter. They live in the ocean.
Their language consists of benign viruses/prions/etc internally synthesized and then released; these then harmlessly "infect" the receiver of the message, and deliver the information. To them, communicating by finding any old molecule and making a bunch of them wiggle ("speaking" as we humans call it) is needlessly confusing. On the other hand, they find communication with light patterns ("text") to be an intriguing concept, and some groups have been developing their own systems that involve glowing various colors in succession (similar to Morse Code, but with colors instead of dots and dashes).
...That's all I've got for now. Now it's your turn to add!