Description

??????????????? (Straight-chain alkane classroom of Rika Nyurikako) is a game where players will try to build simple molecules.
In turn order, each player draws an atom card from the deck and use it to create a new molecule (if they don't have one already) or to expand it. When adding an atom to a molecule, the direction of the chemical bond indicated on the card must be followed (cards can not be flipped sideways). A molecule must be completed to start a new one and score points. Any player creating a peroxide bond (-O-O-) is eliminated from the game. Drawing a 13C isotope allows to start a new molecule even if the previous one is still unfinished. Molecules containing halogen and/or carbon atoms are worth more points.
Once the atom card deck is depleted, victory goes to the player who has tallied the most points.

—user summary

???????????????????????????????????????????????????????????OK?
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??????2????-O-O-????????????????????????????????

—description from the publisher

A molecule is completed with straight carbon atoms as a skeleton. It looks like it's going to be difficult, but if you intuitively connect the hands of the cards, you'll be fine!
I can't stand the sense of accomplishment when a large molecule is completed.
But watch out for -O-O-peroxides with two oxygens in a row! It's a dangerous substance, so it's game over immediately.

—description from the publisher (translated)