I know everyone is rl worried about Supergirl writers turning Lena Luthor evil after that super shady chess scene but I’d like to offer an alternative explanation.
See, when we see Lena playing chess against her brother Lex, she’s actually playing as the white set. Which as we know, symbolically represents the “light” side”.
This foreshadows Lex and Lena being on opposing sides of the battle of good v evil as adults. Lex on the side of dark and Lena the side of light. Not only that, but the piece she uses to move into checkmate?
THE KNIGHT. Which as you may remember, moves in an L pattern. Knights are also symbolic of nobility, courage and honor. A white knight is a saviour. I think it’s highly unlikely to be coincidence that it was the knight that Lena used to defeat Lex. When Lena is in her office after Kara leaves, she picks up that same piece in contemplation.
Lena is looking back on that chess game she had with Lex all those years ago, where she defeated him using the white knight. I think this strongly suggests that Lena herself is the white knight, rather than it being Kara as initial interpretations might suggest.
Instead of this being a “muhahaha, I’m actually an evil mastermind” moment, it symbolises her coming battle against the forces of evil (aka Lillian Luthor). She’s smart and resourceful and she defeated them once,she can do it again. She’s not evil, she’s just an extra ho who is planning to wreck Lillian’s shit.
At least this is what I’m hoping b/c honestly it would be terrible writing at this point to build up a narrative of “it’s not your origin or your genetics that make you, it’s your choices” (mon-el, m’gann), only to destroy it by making Lena evil all along.