Not long into Seed of Life, you'll come across a pedestal that you have to activate by solving a simple rotating puzzle. If you listened closely to the dialogue, Cora mentions inserting the missing petals into the pedestal to make it complete.
Upon doing so, with the two petals, you have on hand. A purple glowing object appears on top of the dais, but alas, you cannot interact with it straight away. Core mentions something about needing some device to interact with it.
Progress with the story, get past those weird blue alien creatures, and make your way to the device on the other side of the tiny ravine. This will give you a Talisman, which is how abilities are used in the game. Once acquired, make your way back to the pedestal, and interact with the purple object. You can now finally interact with it.
This will give Cora her first ability, the Vision capsule, and to use it, you must press Up on the D-Pad or 1 on keyboard. The Vision ability allows you to see things that the naked eye can't see, such as revealing hidden objects, and is how you progress further into Seed of Life.
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