Dream dresses: let’s draft the pattern of this one.
You need some structure on the bodice, so an inner layer with stiff fabric and bones, and a drapey fabric on top, in this case silk velvet.
Start from a basic block with darts and full front.
Redraw the center back shaping it, draw the new hem with the train and the mermaid skirt reducing at the knee.
Draw the slash lines on back and front.
Notice that front skirt is made of two halves that overlap.
Trace the separate pieces.
Close the darts on both waistbands.
On front bodice, draw the neckline.
On both sides reduce 1cm at it by widening the dart.
Reshape waist darts to fit the underbust.
Draw the stile lines for the drape.
Cut away all the extra and the inner part of darts, then cut on all slash lines.
You will get these separate pieces.
Get the two front skirts and draw the slash lines on the right one.
Cut through the lines, close the dart and open the drape volume.
Mark the pleats.
Here is your new pattern!