How did he do this? Because you can't see any soil, you might wonder if this one is a flowering air plant. Though no explanation (nor plant variety) is given, my guess is that there is a pocket of soil nestled out of sight in this piece of driftwood 

One of many things that Robert Steven is know for are his breaks with bonsai convention. Just when you think he has achieved some mastery of a style he's off trying something else

The photos shown here are from Robert's ArtFest on his Missions and Legends 2020 (Facebook)
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Here's Robert's caption with this one... "Nature holds the perfect key to aesthetic, intellectual, cognitive and even spiritual balance; breaking its balance will bring disaster!"

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Robert's ArtFest Quote of Today (April 4th, 2020)
"To create outstanding bonsai, you need to have an understanding of psychology, human behavior, and the little shortcuts, the little quirks, in the way people operate; then you can use them to make it easier for people to engage with your creation."

 Robert's caption "Critics and curators are failed artists." A little harsh but being outspoken comes with the territory

 
This one seems a bit more conventional,
though the pot might have something to say about that 

A metaphor for bonsai? You'll have to click over to read Robert's comment

Robert with one of his unique creations