For borders and shadows that complement your dark magical palette, I recommend using a shade that adds depth and contrast without overpowering the existing colors. Here are a couple of suggestions:

1. Charcoal Gray - A deep gray can provide a subtle yet strong contrast, enhancing the overall design without being too harsh.
2. Dark Bronze - This can add a touch of elegance and warmth, resonating well with the warm gold and rich burgundy.

Here’s how these colors can be represented in your palette:

json
{
  "palette_name": "SpellBound - Borders and Shadows",
  "colors": [
    {
      "name": "Charcoal Gray",
      "hex_code": "
                            
                            #333333
                        "
    },
    {
      "name": "Dark Bronze",
      "hex_code": "
                            
                            #7C4A2B
                        "
    }
  ]
}

Would you like to add these to your existing palette or explore more options?