So almost a 2048 on a hexagon but everything's trying to kill you situation? Interesting. I don't know if I'm missing some strategy or if death is just extremely inevitable.
I found the mouse clicking input to be very unreliable -- only every other click or so would actually "register" and cause me to move. I'm on macos with a high dpi / 120hz display.
Moving your move_player_system out of FixedUpdate and into Update seemed to resolve this. In FixedUpdate, you're potentially missing input events. This was a bit confusing for me since I thought https://github.com/bevyengine/bevy/pull/10077 in bevy 0.12.1 would have covered this, but I don't think that PR did anything with Res<Input>. Just EventReader<MouseButtonInput>.
The game over screen is really cool, but I accidentally immediately clicked past it and missed it like 5 times in a row.