DESCRIPTION
A faster take on gracen's. winning on turn 3 is nice plus gemstone caverns isn't a dead draw since you can discard it . Also the addition to Halimar Depths lets me set up my treasure hunt. With that it can also help set up the combo and it's nice to rearrange the top of your library so I feel 4 is correct when playing a deck that revolves around drawing cards and setting up a combo kill
Basically if you go first you can win on turn 4 by playing as follows
Turn 3 play seismic assault
Turn 4 play Swans of Bryn Argoll and discard lands to target your swan draw lots of cards and throw lands to the opponent's face....
Now if you go second
Hopefully you have a gemstone cavern in hand on the opening turn you can put it in to play .
Turn 2 seismic assault
Turn 3 Swans of Bryn Argoll